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Changing attitudes in community nutrition
Changing Attitudes in Community Nutrition Betty Ruth Carruth and Katherine O. Musgrave A quantifiable tool is applied to measure attitude change about nutrition education Summary The use of a semantic differential instrument for evaluating attitude changes as a result of a university community nutrition course is described. Twenty-five bipolar adjective scales were tested for homogeneity to identify the most appropriate descriptors of community nutrition and nutrition education. Scales such as complete-incomplete, up-to-date-obsolete, widespreadnot prevalent, pleasant-unpleasant, and reliable-unreliable had significant inter-item correlation and were considered evaluative descriptors. It appeared that students' viewpoints ofcommunity nutrition and nutrition education were changed as a result of instruction.
The Measurement of Attitudes In the 1978 position paper regarding the scope and thrust of nutrition education, the American Dietetic Association stated that evaluation must be a part of all nutritional endeavors, with measurable objectives constructed to determine the effectiveness of a program (I). Therefore, any evaluation strategy must necessarily encompass the cognitive, the affective, and the psychomotor domains of learning (2). Agreement exists among educators that tools should be developed to assess program effectiveness (3, 4), and some workers rely more on the measurement of attitudes (5) than of knowledge (6). A recent study showed that knowledge was significantly related to some nutritionrelated attitudes (7). In measuring attitudes, a basic premise is that reading about a concept or "construct," as it is called by sociologists, elicits some feeling about that construct. This feeling is then recorded on some type of scale or series of numbers that indicate the degree of a person's feeling about that concept or construct. In recent publications about attitude research in nutrition education, a Likert-type instrument has been used frequently. With the Likert-type format, an individual responds to a group of statements on a continuum from strongly agree to strongly disagree, with an inherent judgment on the part of an individual as to what the total statement means. The greater the proportion of like responses to anyone statement, the more similar are the attitudes held by the group surveyed. Some dissatisfaction with this method has been reported because the words used in context of a statement can bias the response (8). One of the major difficulties in assessing self-reported attitudes is to develop statements that involve a single construct rather than the multiple constructs which may occur in a single attitude statement. For example, the statement "Nutrition should be taught in science classes" can be judged in a number of ways. The individual's feelings toward the constructs of science, nutrition, teaching and teachers, and science classes in general may singly or as a group of constructs elicit a strongly agree or disagree response. Thus, multiple constructs can confound the interpretation of any group scores. In order to eliminate the associative quality of words, scales composed of
THE A UTHORS are, respectively, Director ofNutrition, Multidisciplinary Adolescent Health Training Project, Department of Pediatrics, Southwestern Medical School, Dallas, TX 75235; and Associate Professor in Food and Nutrition, University of Maine, Orono, ME 04469.
bipolar adjectives have been used to describe attitudes (9). A person responds to pairs of adjectives rather than words in the context of a sentence or phrase. These scales are called semantic differentials (S.D.). The purpose of this paper is to describe the results of a study utilizing the semantic differential as an attitude assessment tool in a community nutrition course. The objectives of the study were: • To identify the changes or the measurable trends over time in attitudes toward the two constructs of community nutrition and nutrition education • To select those scales that significantly reflected individuals' attitudes about community nutrition and nutrition education as a result of instructions. Attitude assessment. Attitude has been described as an underlying disposition which enters along with other influences into the determination of a variety of behaviors toward an object or class of objects, including statements of beliefs and feelings about the object and approach-avoidance actions with respect to it (10). A useful attitude scale must possess the properties of reliability, validity, unidimensionality, equality of units, and a zero point (11). Unidimensionality is the property that indicates that a single attitude is being measured. Reliability is an indicator of the reproducibility of test results from a series of measurements from a given sample. Equality of units implies that the ratings are equally more than or less than a reference point whereas a zero point gives the respondent a reference point for describing an attitude as being less favorable or more favorable. The problems encountered in the choice of an attitude measurement instrument have been described (8). Semantic differential. The semantic differential was designed to measure individuals' reactions to semantic objects utilizing ratings of bipolar adjectives called scales. Although some studies by Osgood, Tannenbaum, and Suci focused on reactions to stimulus words, as work progressed, the possible association with attitudes was examined. It was found that after many replications the three basic dimensions accounting for most of the covariation in subjects' responses were evaluation, potency, and activity (12). Evaluation involves paired adjectives such as goodbad; potency relates to power (strong-weak); and activity, to pairs such as slow-fast. Other researchers have shown the value of applying the semantic differential to attitude measurement (11, 13). An attitude scale for measuring public opinion was developed involving paired adjectives from the semantic differential, and it was concluded that there is almost always an evaluation factor present in the data. The evaluative factor was determined by respondents ranking adjective pairs such as good-bad, reliable-worthless, honest-dishonest, and fair-unfair. Reported correlation coefficients for various paired adjectives making up the evaluation factor ranged from r = 0.79 to 0.88. This means that respondents rated the paired adjective scales similarly and thus held relatively similar attitudes toward the opinions measured (13). The semantic differential has been employed in the evaluation of faculty and of students and in the measurement of attitude July-September 1979
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Content Areas Covered in Community Nutrition Course 1 Public health terminology 2 Description of the role of the community nutritionist as a member of health team 3 Recognition of the significance of assessing dietary adequacy of individuals and groups as an integral component of the community health care program 4 Identification of methods of assessment of nutritional status 5 Identification of high-risk groups in the community based on biochemical and statistical data 6 Identification of organizations involved in the provision of health care, including nutrition at local, state, federal, and international levels 7 Description of the general responsibility of health care organizations 8 Description of the nutritionist's function as an educator, program planner, and facilitator of change
Figure 1
toward school subjects (14-16). The semantic differential was utilized to measure relationships among four constructs in teacher evaluation and was found to be an effective method to examine the interrelationships among the constructs of teacher credibility, content, delivery, and feedback (14). The semantic differential has been recommended as a means of assessing students' affective behavior because it possesses a great deal offlexibility, is easy to construct, and is simple to score (17). The semantic differential technique was employed in collecting data from 1,085 individuals to describe and assess the climate of professional library education in the northeastern section of the U.S. Three bipolar adjective pairs accounted for 77.3010 of the variance and one pair accounted for 22.7% of the variance in responses (18). Although numerous results were published in other disciplines (19, 20), an intensive search of the literature did not reveal the use of the semantic differential in the areas of community nutrition and/or nutrition education.
Population and Procedures All students enrolling in a community nutrition course for the years 1975-78 were asked to complete a three-page form. The front page gave instructions for responding to paired adjective scales for the two constructs of community nutrition and nutrition education as listed on pages two and three, respectively. Out of 193 students officially enrolled at the beginning of the four quarters, 188 completed the forms. At the end of each quarter, the same forms were administered for the years 1975-78, resulting in 105 usable responses. Intergroup means were not significantly different; as a result, responses were pooled for future factor analysis. The course could be taken by any university student who met the prerequisites of one course in the principles of nutrition and six credits of psychology, sociology, anthropology, or economics. The students were primarily nutrition and dietetic majors, although other disciplines were represented. Course content and procedures. The university catalogue described the course as dealing with nutrition and health practices of the family in the community: concepts and methodologies for nutrition education. The course content is shown in Figure I. 128
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To enable students to achieve stated behavioral objectives of the course, public health information, various methods of nutrition education, and social and psychological theories of change were presented. Current resource materials were introduced, and practicing community nutritionists served as guest speakers. Students attended lectures for 45 minutes, 3 times a week, during an II-week winter quarter. Students were given the opportunity to apply their knowledge and understanding of communication theories and principles of learning in a simulated community nutrition education experience. They judged and evaluated selected nutrition education materials developed for the lay public, including the calculation of the literacy level required to read the published materials. Current bibliographies were provided, and students were required to write a paper meeting publication guidelines of the
Journal of Nutrition Education. Assessing attitudes with semantic differential scales. Rating forms were developed after the manner of Osgood et al. (12). An assumption of reliability and .validity was based on the numerous published data, as previously cited, which demonstrated that an evaluation factor could be tapped using scales such as good-bad and essential-nonessential. The semantic differential also meets the criteria of equal units and a zero point. It was assumed that factor analysis of students' responses would provide information about the unidimensionality of the scales as descriptors of the constructs of nutrition education and community nutrition. A separate sheet was provided for each construct with the listing of 25 bipolar adjective scales. The order of a favorable to a less favorable rating was reversed randomly to avoid a pattern of scoring. Scales included some adjectives as nondiscriminatory items, not specifically relevant to research purposes. A sample instruction page is shown in Figure 2. Administration. The semantic differential was administered during the first and last weeks of the II-week winter quarter for the years 1975-78. Identical forms were used each year. In further discussion these administrations will be referred to as preand postratings. Analysis of data. The raw data were transferred to IBM cards from the student responses on the bipolar scales. Ratings were assigned with one to seven points (12). Four was neutral, and Figure 2 Excerpt from an instruction page for the use of semantic differential in evaluation of course in community nutrition
Instruction Page (Excerpt)' In taking this instrument, please make your judgments on the basis of what these concepts mean to you. On each page you will find a different idea to be judged and beneath it a set of scales. If you feel that the concept Nutrition Community is very closely related to one end of the scale, you should place your check mark as follows: valuable~:
__: __: __: __: __: __ : worthless
valuable __: __: __: __: __: __ :~: worthless The direction toward which you check, of course, depends upon which of the two ends of the scale seem most characteristic of the thing you are judging. 1
Complete instructions also provided the respondent with opportunity to give neutral and intermediate responses.
Table 1 Scales indicating trends in attitudes toward community nutrition at beginning and completion of quarter Scales
Factor I Correlation Coefficient Pre (n= 188)
Pleasant-unpleasant Complete-incomplete Up-to-date-behind-the-times Good-bad Reliable-unreliable Widespread-not prevalent Flexible-rigid Realistic-idealistic Valuable-worthless Up-to-date-obsolete Labor saving-wasteful Suitable-unsuitable Essential-nonessential Fast-slow Visionary-shortsighted Powerful-weak Significant-insignificant Exciting-dull Orderly-chaotic Reassuring-frightening Eigenvalues Variance
.222 .065 .055 .374 .267 .026 .362 .298 .818.210 .405.483.627.059 .263 .336 .568· .562· .020 .150 6.609 (J2=0.60
Factor II Correlation Coefficient
Post (n = 105)
.518.458.404.222 .477.573.086 .314 .079 .512.439.179 .120 .654.465.541.171 .315 .647.676· 8.827 (J2=0.63
Pre
.256 .306 .296 .237 .535.116 .261 .438.194 .268 .348 .248 .043 .271 .555 .191 .217 .107 .504.510· 1.775 (J2=0.164
Post
.513.206 .354 .742.426.164 .450.004 .693.227 .080 .180 .472.070 .227 .277 .388 .582.049 .267 1.471 q2=0.105
• r"2.40
one was the lowest score for each bipolar adjective scale. Respondents were instructed to furnish correct social security numbers in order to match the ratings of each student for the beginning and conclusion of each quarter. However, many either failed to list the digits in the exact same order or left out the numbers completely. Data were analyzed using the Statistical Package for the Social Sciences (21). Responses were analyzed using a varimax rotated factor matrix. Factor analysis results in locating each construct, such as nutrition education, in semantic space - a space with an undetermined number of dimensions but with a common origin or zero point for all scales. This type of analysis is a means of finding a "set of dimensions" which account for relationships among variables. These dimensions are described in terms offactors or axes. A factor is chosen so that the sum of squared projections of the vectors on that factor can be a maximum, thus explaining the greatest possible proportion of the variance. An eigenvalue (variance) is the sum of the squared correlations between the variables and a factor. Eigenvalues give the amount of variance from the original correlation matrix, which is explained by each successive factor (21).
Trends in Attitudes Community nutrition. Results given in Table 1 show that students' responses to scales differed over time. Initially, the construct of community nutrition was viewed as valuable, laborsaving, suitable, essential, significant, and exciting. At the conclusion of the course the significant descriptors included pleasant, complete, up-to-date (as opposed to both behind-thetimes and obsolete), reliable, widespread, labor-saving, fast, visionary, powerful, orderly, and reassuring. As a result of instruction, students viewed community nutrition in a different manner, particularly in regard to items six, seven, and eight listed in Figure 1. In general, students had limited awareness of health care organizations at local, state, or federal levels. Thus, it is felt that by the end of the quarter they had increased awareness and tended to mark a larger number of scales such as up-to-date, widespread, orderly, and reassuring
because programs accessible to high-risk groups were stressed during the instructional phase. Also, the responses were to be used for evaluation purposes; and the potency and activity dimensions of the semantic differential were not of particular value in this study. In addition, with the number of responses (n> 100), a correlation coefficient of 0.20 would be significant at p< .05. However, this results in a less discriminating instrument for evaluation. If r = 0.20 were acceptable, then several scales would appear on both the pre- and postratings as significant contributors to the evaluative factor (Factor I). The reaction to labor-saving may relate to class discussions about referrals for community programs and the interrelation of health services. Also, the teaching emphasis on current literature is likely reflected in ratings as orderly, reliable, visionary, and reassuring. This first factor (Factor I) was associated with scales considered to be evaluative in the beginning of the quarter and to include power at the conclusion of the quarter. Factor I accounted for 60% of the variance at the beginning and 63U1o of the variance at the conclusion of the quarter. According to one researcher, the large eigenvalue and the percent of variance should identify Factor I as the evaluative dimension of community nutrition (12). The second factor accounted for 16.4U1o of the variance in the initial rating, and the scales with high correlation coefficients were those that described community nutrition as being reliable, realistic, visionary, orderly, and reassuring. In the rating at the conclusion of the quarter, the heavily loaded scales in Factor II had changed to pleasant, good, reliable, flexible, valuable, essential, and exciting and accounted for 1O.5U1o of the variance. Thus, at both the beginning and conclusion of the course, about 75U1o of the variance was explained by the two factors. Nutrition education. Table 2 involves ratings for the construct nutrition education. The correlation among scales made up of bipolar adjectives also differed over time. At the beginning of the quarter, nutrition education was viewed as pleasant, valuable, essential, significant, and exciting. At the conclusion of the quarter, the students viewed nutrition education as complete, July-September 1979
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Table 2 Scales indicating trends in attitudes toward nutrition education at beginning and conclusion of quarter
Scales Pleasant-unpleasant Complete-incomplete Up-to-date-behind-the-times Good-bad Reliable-unreliable Widespread-not prevalent Flexible-rigid Valuable-worthless Up-to-date-obsolete Essential-nonessential Visionary-shortsighted Powerful-weak Significant-insignificant Exciting-dull Orderly-chaotic Accessible-inaccessible Reassuring-frightening
Eigenvalues Variance
*
r~
Factor I Correlation Coefficient Pre (n: 188)
Post (n: 105)
Pre
Post
.408* .026 .024 .298 .210 .142 .117 .817* .169 .745* .100 .254 .430* .505* .048 .194 .150
.073 .455* .710* .587* .478* .108 .183 .306 .617* .051 .418* .170 .342 .348 .583* .248 .510*
.326 .084 .046 .324 .307 .272 .426* .160 .095 .130 .316 .532* .278 .312 .433* .515* .676*
.273 .356 .294 .068 .500* .627* .215 .033 .327 .131 .605* .577* .497* .329 .299 .533* .267
5.844 (Jl:.516
7.335 (Jl:.562
1.934 (Jl: .171
1.489 (Jl:.114
.40
up-to-date, good, reliable, vtSlonary, orderly, and reassuring. Instruction appeared to provide a framework in which a) current educational problems were identifiable (complete, up-to-date); b) sequencing for action was identified (orderly, visionary); and c) cognitive knowledge was applied toward problem solving (reliable, reassuring). The students may have used the words "pleasant" and "valuable" much like reading a good novel is pleasant or valuable. However, as future nutritionists, instruction seemed to result in attitudes which were oriented toward what nutrition education should be, i.e., up-to-date and complete. The evaluation factor (Factor I) explained 51.6070 of the variance at the beginning of the quarter as compared with 56.2070 of the variance following instruction. Factor II accounted for 17.1070 of the variance at the beginning, and 11.4070 of the variance at the conclusion. About 69070 of the variance was associated with Factors I and II; however, the evaluation factor is of primary importance in this study. In rating community nutrition and nutrition education, the power and the activity dimensions were not clearly shown. This can be explained on the basis that evaluative adjectives were selected purposefully and that a relatively homogeneous rating occurred postinstructional. Although correlation coefficients for the paired adjectives "powerful-weak" contributed significantly to Factor II, the other paired adjectives were more descriptive of an evaluative rather than a power dimension. The students responded primarily in evaluative terms, which was compatible with ideas that a semantic differential can provide affective evaluation of a community nutrition course.
Changes in Ratings Over Time Factor analyses provide information about inter-item correlations among the paired adjective scales. However, it does not identify the direction of change or proportion of change over time. In this study, it was important to examine the direction of change and significance of change in the ratings over time. Individuals' ratings were matched, using social security numbers and full completion of the S.D. forms. Any missing responses, inverted or missing digits, or multiple markings resulted in exclusion of that datum. As a result, 88 responses were exam130
Factor II Correlation Coefficient
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ined for proportion of change and the significance of change (Table 3). The direction of the change during the quarter is indicated by the appropriate plus or minus sign. The students perceived community nutrition as being more complete, up-todate, widespread, flexible, and orderly at the completion of the quarter. For each of these significant scales rated positively, the proportion of change was 60070 or greater. The frequency tables constructed for the McNemar tests provided the researchers with a type of item analysis that could prove to be valuable in future decisions about course content. Such examples are given in Figure 3 where responses to three scales on community nutrition are compared. The percentages associated with the valuable-worthless scale in Figure 3a show a low proportion of change as contrasted with the powerful-weak scale in Figure 3b, which indicated a widespread proportion of change. Neither of these scales showed sufficient differences in change of direction to be significant, according to McNemar's test, at the p~O.OOI level whereas in Figure 3c the proportion for the widespread-prevalent scale is highly significant at the p ~ .001 level. Forty-seven of the 88 respondents increased the rating toward "widespread," and only 15 students' ratings decreased toward "not prevalent" with 26 respondents showing no change. The scales that showed significant change when applied to nutrition education were pleasant-unpleasant, realisticidealistic, valuable-worthless, and significant-insignificant. It can be seen in Table 3 that the proportion and direction of change in the rating of the two constructs was similar, but the same scales were not significant for community nutrition and nutrition education.
Implications for Evaluation Strategies The overall purpose of this research was to utilize the semantic differential as a rating tool for evaluation purposes and to determine changes or trends in attitudes as a result of instruction. The findings indicate that pre- and postresponses to certain pairedadjective scales were statistically significant. For example, the scales with such descriptors as up-to-date, complete, widespread, and orderly were significant using factor analysis of McNemar's tests for proportion of change. This was not true for
(a)
(b)
Valuable-Worthless 5=0.353 (-) P=36.36
Powerful-Weak 5=1.133(+) P=71.59
N.S.
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Widespread-Not Prevalent
N.S.
5=4.06 (+) P=70.45
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Figure 3 Percentage of students' responses on pre- and postratings for community nutrition. On the abscissa the intervals of the scales are recorded. On the ordinate the percentage responses from the cross tabulations are compared. The significance of change (5) was determined by McNemar's test and the proportion of change (P). *
= Number decreasing rating from pre to post N; = Number increasing rating from pre to post N no = Number with same response Nd
Table 3 Proportion and significance of change for pre- and postratings of community nutrition and nutrition education
Scales
Timely-untimely Pleasant-unpleasant Unusual-ordinary Advanced-elementary Complete-incomplete Up-to-date-behind-the-times Good-bad Reliable-unreliable Widespread-not prevalent Flexible-rigid Realistic-idealistic Valuable-worthless Fashionable-outmoded Up-to-date-obselete Labor-saving-wasteful Suitable-unsuitable Essential-nonessential Fast-slow Visionary-shortsighted Powerful-weak Significant-insignificant Exciting-dull Orderly-chaotic Accessible-inaccessible Reassuring-frightening • p:S.05
•• p:s .01
Community Nutrition (n = 88)
Nutrition Education (n = 91)
Significance of Change
Significance of Change
.142 (-) 1.408(-) .130(+) .516 (+) 3.812 (+)** 2.885 (+)** 1.021 (+) .420 (+) 4.066 (+)** 1.809 ( + ) .943 (-) .353 (-) .816 (+) 1.872 ( + ) .294 (+) .137 (+) .708 (-) .662 (-) .848 (+ +) 1.133 ( + ) .848 (-) 1.213 (-) 2.139 (+)* 1.152 (+) .674 (+)
Proportion of Change 55.68010 69.32 67.04 68.18 70.45 60.23 53.41 57.95 70.45 68.18 62.50 36.36 61.36 63.64 52.27 60.22 36.78 64.77 56.82 71.59 56.82 62.50 63.64 69.32 62.51
1.474 ( - ) 2.142 (-)* .534 (-) .124 (-) 1.116(+) .662 (-) 1.067 (+) .137 (+) 1.861 (+) .130 (+) 3.414 (-)** 3.413 (-)** 1.387 (+) .662 (-) .980 (-) 1.051 (-) 1.095 (-) .134 (+) .128(+) .816(-) 2.949 (-)** 1.664 (-) .384 (+) .911 (-) .911 (+)
Proportion of Change 50.55% 53.80 61.54 71.40 71.43 62.64 47.25 58.24 71.43 64.84 63.74 34.06 57.14 62.64 56.67 63.74 32.96 60.44 67.03 59.34 50.55 67.03 67.03 64.83 64.83
••• p:s .001
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a number of other scales because of the criteria set by the investigators. It is important to emphasize that the correlation coefficient required for inclusion of scales in the factor analysis, r = 0.40 as being significant, may be unnecessarily high. In truth, for the pre-instruction responses (n = 188), a correlation coefficient of r ~ 0.20 is statistically significant at p $ .01. Therefore, if a coefficient of r ~ 0.20 were acceptable to the investigators, many more paired-adjective scales could be considered as significant descriptors of both constructs, i.e., community nutrition and nutrition education. However, it is well recognized that response fatigue sets in when individuals are required to complete extensive rating scales. Therefore, selecting fewer scales is desirable. The findings also demonstrate that the selection of scales for a postevaluation tool should include all statistically significant scales which explain most of the variance and contribute to the unidimensionality of the scales. For community nutrition, 12 scales with evaluative descriptors had coefficients of r ~ 0.40 on Factor 1 (posttest) whereas nutrition education had eight scales on Factor I (posttest) meeting the criterion and reflecting an evaluative dimension. It is preferable to use fewer scales when most of the variance can be accounted for rather than to adminster the 25 scales consisting of bipolar adjectives. In terms of applied findings, a major component of this study involves an analysis of directional change for attitudes. Correlation coefficients indicate whether or not a change is significant, but do not provide the teacher with information about the positive or negative aspects of that change. As shown in Table 3 and Figure 3, the direction, proportion, and significance of change was determined by applying McNemar's test. Cross tabulations provided frequencies of numbers of students increasing, decreasing, or not changing the marking of each scale. This type of analysis has applications for course development and implementation because a series of evaluations over several quarters and/or years could form a basis for comparison. Modification in course content, teaching methods, and/or variations, when different teachers are assigned to a course, are likely to be reflected in students' attitudes toward that course, such as upto-date, complete, and widespread. It is recommended, therefore, that responses be analyzed for changes over time, indicating that attitudes have changed and what the direction of that change is. In summary, students increased the marking significantly on a number of scales on the construct of community nutrition. As a result of instruction, students' viewpoints toward the constructs of community nutrition and nutrition education were changed. 0
Acknowledgment This project was partially supported by the University of Minnesota Computer Center, Minneapolis, MN 55455.
References I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
17 18 19 20 21
Note This article is Scientific Journal Series No. 10,395, University of Minnesota Agricultural Experiment Station.
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Position paper on the scope and thrust of nutrition education, J. Am. Dietel. Assn., 72:302, 1978. Bloom, B. S., Human Characteristics and School Learning, McGraw-Hill, New York, 1976. Schwartz, N. E., and S. Barr, Mothers- Their attitudes and practices in perinatal nutrition, J. Nutr. Ed., 9:169, 1977. Bowering, J. et aI., Influence of a nutrition education program on infant nutrition in East Harlem, J. Am. Dietel. Assn., 72:393, 1978. Schutz, H. G., S. M. Moore, and M. H. Rucker, Predicting food purchase and use by multivariate attitudinal analysis, Food Tech., 31:568, 1977. Krause, T. 0., and H. M. Fox, Nutrition knowledge and attitudes of physicians, J. Am. Dietel. Assn., 70:607, 1977. Grotkowski, M. L., and L. S. Sims, Nutritional knowledge, attitudes and dietary practices of the elderly, J. Am. Dietel. Assn., 72:499, 1978. Carruth, B. R., and H. L. Anderson, Scaling criteria in developing and evaluating an attitude instrument, J. Am. Dietel. Assn., 70:42, 1977. Snider, J. G., and C. E. Osgood, Semantic Differential Technique, Aldine Publishing Co., Chicago, 1969. Cook, S. W., and C. Selltiz, A multiple indicator-approach to attitude measurement, Psych. Bull., 62:36, 1964. Shaw, M. E., and J. M. Wright, Scales for the measurement ofattitudes, McGraw-Hill, New York, 1967, pp. 1-32. Osgood, C. E., G. J. Suci, and P. H. Tanenbaum, The Measurement of Meaning, University of Illinois Press, Urbana, 1965, pp. 76-216. Brinton, J. E., Deriving an attitude scale from semantic differential data, Public Opinion QuarL, 25:289, 1961. McDowell, E. E., The semantic differential as a method of teacher evaluation, J. Ed. Res., 68:330, 1975. White, W. F., and M. de la Serna, Students' ratings of their instructors and the instructors' ratings of students in educational psychology, J. Psych., 92: 195, 1976. Nowacek, G. A., Validation of the Semantic Differential as a Measure of One Element of Affective Education: Attitude toward school subjects, Ph.D. dissertation, University of Michigan, Ann Arbor, 1976. Simpson, R. D., Assessing student behavior in the affective domain, Eng. Ed., 68:397, 1978. Sywak, M., A Study of Involvement and Consensus in Graduate Professional Library Education Using the Semantic Differential, Ph.D. dissertation, New York University, New York, 1977. Schutz, R. W., and F. L. Smoll, Equivalence of two inventories for assessing attitudes toward physical activity, Psych. Rep., 40: 1031, 1977. Summers, G. F., Attitude Measurement, Rand McNally & Co., Chicago, 1970, pp. 235-253. Nie, N. H. et aI., Statistical Package for the Social Sciences, 2d ed., McGraw-Hill, New York, 1975, pp. 468-514. Conover, W. L, Practical Nonparametric Statistics, John Wiley & Sons, New York, 1971, pp. 127-130.
ELEMENTARY
Approximately 225 printed and audiovisual materials are included in this updated resource. Those involved in teaching nutrition to elementary level students will find the selected materials useful as teaching tools and informational references. Entries for materials produced after 1974 are annotated with JNE review references cited. Titles and Spanish language items are indexed separately. Before October 1, 1979 $4.00
TEACHING MATERIALS
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132
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Vol. 11 No.3
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AND
TEACHER REFERENCES
::R.evised
The Measurement of Attitudes In the 1978 position paper regarding the scope and thrust of nutrition education, the American Dietetic Association stated that evaluation must be a part of all nutritional endeavors, with measurable objectives constructed to determine the effectiveness of a program (I). Therefore, any evaluation strategy must necessarily encompass the cognitive, the affective, and the psychomotor domains of learning (2). Agreement exists among educators that tools should be developed to assess program effectiveness (3, 4), and some workers rely more on the measurement of attitudes (5) than of knowledge (6). A recent study showed that knowledge was significantly related to some nutritionrelated attitudes (7). In measuring attitudes, a basic premise is that reading about a concept or "construct," as it is called by sociologists, elicits some feeling about that construct. This feeling is then recorded on some type of scale or series of numbers that indicate the degree of a person's feeling about that concept or construct. In recent publications about attitude research in nutrition education, a Likert-type instrument has been used frequently. With the Likert-type format, an individual responds to a group of statements on a continuum from strongly agree to strongly disagree, with an inherent judgment on the part of an individual as to what the total statement means. The greater the proportion of like responses to anyone statement, the more similar are the attitudes held by the group surveyed. Some dissatisfaction with this method has been reported because the words used in context of a statement can bias the response (8). One of the major difficulties in assessing self-reported attitudes is to develop statements that involve a single construct rather than the multiple constructs which may occur in a single attitude statement. For example, the statement "Nutrition should be taught in science classes" can be judged in a number of ways. The individual's feelings toward the constructs of science, nutrition, teaching and teachers, and science classes in general may singly or as a group of constructs elicit a strongly agree or disagree response. Thus, multiple constructs can confound the interpretation of any group scores. In order to eliminate the associative quality of words, scales composed of
THE A UTHORS are, respectively, Director ofNutrition, Multidisciplinary Adolescent Health Training Project, Department of Pediatrics, Southwestern Medical School, Dallas, TX 75235; and Associate Professor in Food and Nutrition, University of Maine, Orono, ME 04469.
bipolar adjectives have been used to describe attitudes (9). A person responds to pairs of adjectives rather than words in the context of a sentence or phrase. These scales are called semantic differentials (S.D.). The purpose of this paper is to describe the results of a study utilizing the semantic differential as an attitude assessment tool in a community nutrition course. The objectives of the study were: • To identify the changes or the measurable trends over time in attitudes toward the two constructs of community nutrition and nutrition education • To select those scales that significantly reflected individuals' attitudes about community nutrition and nutrition education as a result of instructions. Attitude assessment. Attitude has been described as an underlying disposition which enters along with other influences into the determination of a variety of behaviors toward an object or class of objects, including statements of beliefs and feelings about the object and approach-avoidance actions with respect to it (10). A useful attitude scale must possess the properties of reliability, validity, unidimensionality, equality of units, and a zero point (11). Unidimensionality is the property that indicates that a single attitude is being measured. Reliability is an indicator of the reproducibility of test results from a series of measurements from a given sample. Equality of units implies that the ratings are equally more than or less than a reference point whereas a zero point gives the respondent a reference point for describing an attitude as being less favorable or more favorable. The problems encountered in the choice of an attitude measurement instrument have been described (8). Semantic differential. The semantic differential was designed to measure individuals' reactions to semantic objects utilizing ratings of bipolar adjectives called scales. Although some studies by Osgood, Tannenbaum, and Suci focused on reactions to stimulus words, as work progressed, the possible association with attitudes was examined. It was found that after many replications the three basic dimensions accounting for most of the covariation in subjects' responses were evaluation, potency, and activity (12). Evaluation involves paired adjectives such as goodbad; potency relates to power (strong-weak); and activity, to pairs such as slow-fast. Other researchers have shown the value of applying the semantic differential to attitude measurement (11, 13). An attitude scale for measuring public opinion was developed involving paired adjectives from the semantic differential, and it was concluded that there is almost always an evaluation factor present in the data. The evaluative factor was determined by respondents ranking adjective pairs such as good-bad, reliable-worthless, honest-dishonest, and fair-unfair. Reported correlation coefficients for various paired adjectives making up the evaluation factor ranged from r = 0.79 to 0.88. This means that respondents rated the paired adjective scales similarly and thus held relatively similar attitudes toward the opinions measured (13). The semantic differential has been employed in the evaluation of faculty and of students and in the measurement of attitude July-September 1979
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Content Areas Covered in Community Nutrition Course 1 Public health terminology 2 Description of the role of the community nutritionist as a member of health team 3 Recognition of the significance of assessing dietary adequacy of individuals and groups as an integral component of the community health care program 4 Identification of methods of assessment of nutritional status 5 Identification of high-risk groups in the community based on biochemical and statistical data 6 Identification of organizations involved in the provision of health care, including nutrition at local, state, federal, and international levels 7 Description of the general responsibility of health care organizations 8 Description of the nutritionist's function as an educator, program planner, and facilitator of change
Figure 1
toward school subjects (14-16). The semantic differential was utilized to measure relationships among four constructs in teacher evaluation and was found to be an effective method to examine the interrelationships among the constructs of teacher credibility, content, delivery, and feedback (14). The semantic differential has been recommended as a means of assessing students' affective behavior because it possesses a great deal offlexibility, is easy to construct, and is simple to score (17). The semantic differential technique was employed in collecting data from 1,085 individuals to describe and assess the climate of professional library education in the northeastern section of the U.S. Three bipolar adjective pairs accounted for 77.3010 of the variance and one pair accounted for 22.7% of the variance in responses (18). Although numerous results were published in other disciplines (19, 20), an intensive search of the literature did not reveal the use of the semantic differential in the areas of community nutrition and/or nutrition education.
Population and Procedures All students enrolling in a community nutrition course for the years 1975-78 were asked to complete a three-page form. The front page gave instructions for responding to paired adjective scales for the two constructs of community nutrition and nutrition education as listed on pages two and three, respectively. Out of 193 students officially enrolled at the beginning of the four quarters, 188 completed the forms. At the end of each quarter, the same forms were administered for the years 1975-78, resulting in 105 usable responses. Intergroup means were not significantly different; as a result, responses were pooled for future factor analysis. The course could be taken by any university student who met the prerequisites of one course in the principles of nutrition and six credits of psychology, sociology, anthropology, or economics. The students were primarily nutrition and dietetic majors, although other disciplines were represented. Course content and procedures. The university catalogue described the course as dealing with nutrition and health practices of the family in the community: concepts and methodologies for nutrition education. The course content is shown in Figure I. 128
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To enable students to achieve stated behavioral objectives of the course, public health information, various methods of nutrition education, and social and psychological theories of change were presented. Current resource materials were introduced, and practicing community nutritionists served as guest speakers. Students attended lectures for 45 minutes, 3 times a week, during an II-week winter quarter. Students were given the opportunity to apply their knowledge and understanding of communication theories and principles of learning in a simulated community nutrition education experience. They judged and evaluated selected nutrition education materials developed for the lay public, including the calculation of the literacy level required to read the published materials. Current bibliographies were provided, and students were required to write a paper meeting publication guidelines of the
Journal of Nutrition Education. Assessing attitudes with semantic differential scales. Rating forms were developed after the manner of Osgood et al. (12). An assumption of reliability and .validity was based on the numerous published data, as previously cited, which demonstrated that an evaluation factor could be tapped using scales such as good-bad and essential-nonessential. The semantic differential also meets the criteria of equal units and a zero point. It was assumed that factor analysis of students' responses would provide information about the unidimensionality of the scales as descriptors of the constructs of nutrition education and community nutrition. A separate sheet was provided for each construct with the listing of 25 bipolar adjective scales. The order of a favorable to a less favorable rating was reversed randomly to avoid a pattern of scoring. Scales included some adjectives as nondiscriminatory items, not specifically relevant to research purposes. A sample instruction page is shown in Figure 2. Administration. The semantic differential was administered during the first and last weeks of the II-week winter quarter for the years 1975-78. Identical forms were used each year. In further discussion these administrations will be referred to as preand postratings. Analysis of data. The raw data were transferred to IBM cards from the student responses on the bipolar scales. Ratings were assigned with one to seven points (12). Four was neutral, and Figure 2 Excerpt from an instruction page for the use of semantic differential in evaluation of course in community nutrition
Instruction Page (Excerpt)' In taking this instrument, please make your judgments on the basis of what these concepts mean to you. On each page you will find a different idea to be judged and beneath it a set of scales. If you feel that the concept Nutrition Community is very closely related to one end of the scale, you should place your check mark as follows: valuable~:
__: __: __: __: __: __ : worthless
valuable __: __: __: __: __: __ :~: worthless The direction toward which you check, of course, depends upon which of the two ends of the scale seem most characteristic of the thing you are judging. 1
Complete instructions also provided the respondent with opportunity to give neutral and intermediate responses.
Table 1 Scales indicating trends in attitudes toward community nutrition at beginning and completion of quarter Scales
Factor I Correlation Coefficient Pre (n= 188)
Pleasant-unpleasant Complete-incomplete Up-to-date-behind-the-times Good-bad Reliable-unreliable Widespread-not prevalent Flexible-rigid Realistic-idealistic Valuable-worthless Up-to-date-obsolete Labor saving-wasteful Suitable-unsuitable Essential-nonessential Fast-slow Visionary-shortsighted Powerful-weak Significant-insignificant Exciting-dull Orderly-chaotic Reassuring-frightening Eigenvalues Variance
.222 .065 .055 .374 .267 .026 .362 .298 .818.210 .405.483.627.059 .263 .336 .568· .562· .020 .150 6.609 (J2=0.60
Factor II Correlation Coefficient
Post (n = 105)
.518.458.404.222 .477.573.086 .314 .079 .512.439.179 .120 .654.465.541.171 .315 .647.676· 8.827 (J2=0.63
Pre
.256 .306 .296 .237 .535.116 .261 .438.194 .268 .348 .248 .043 .271 .555 .191 .217 .107 .504.510· 1.775 (J2=0.164
Post
.513.206 .354 .742.426.164 .450.004 .693.227 .080 .180 .472.070 .227 .277 .388 .582.049 .267 1.471 q2=0.105
• r"2.40
one was the lowest score for each bipolar adjective scale. Respondents were instructed to furnish correct social security numbers in order to match the ratings of each student for the beginning and conclusion of each quarter. However, many either failed to list the digits in the exact same order or left out the numbers completely. Data were analyzed using the Statistical Package for the Social Sciences (21). Responses were analyzed using a varimax rotated factor matrix. Factor analysis results in locating each construct, such as nutrition education, in semantic space - a space with an undetermined number of dimensions but with a common origin or zero point for all scales. This type of analysis is a means of finding a "set of dimensions" which account for relationships among variables. These dimensions are described in terms offactors or axes. A factor is chosen so that the sum of squared projections of the vectors on that factor can be a maximum, thus explaining the greatest possible proportion of the variance. An eigenvalue (variance) is the sum of the squared correlations between the variables and a factor. Eigenvalues give the amount of variance from the original correlation matrix, which is explained by each successive factor (21).
Trends in Attitudes Community nutrition. Results given in Table 1 show that students' responses to scales differed over time. Initially, the construct of community nutrition was viewed as valuable, laborsaving, suitable, essential, significant, and exciting. At the conclusion of the course the significant descriptors included pleasant, complete, up-to-date (as opposed to both behind-thetimes and obsolete), reliable, widespread, labor-saving, fast, visionary, powerful, orderly, and reassuring. As a result of instruction, students viewed community nutrition in a different manner, particularly in regard to items six, seven, and eight listed in Figure 1. In general, students had limited awareness of health care organizations at local, state, or federal levels. Thus, it is felt that by the end of the quarter they had increased awareness and tended to mark a larger number of scales such as up-to-date, widespread, orderly, and reassuring
because programs accessible to high-risk groups were stressed during the instructional phase. Also, the responses were to be used for evaluation purposes; and the potency and activity dimensions of the semantic differential were not of particular value in this study. In addition, with the number of responses (n> 100), a correlation coefficient of 0.20 would be significant at p< .05. However, this results in a less discriminating instrument for evaluation. If r = 0.20 were acceptable, then several scales would appear on both the pre- and postratings as significant contributors to the evaluative factor (Factor I). The reaction to labor-saving may relate to class discussions about referrals for community programs and the interrelation of health services. Also, the teaching emphasis on current literature is likely reflected in ratings as orderly, reliable, visionary, and reassuring. This first factor (Factor I) was associated with scales considered to be evaluative in the beginning of the quarter and to include power at the conclusion of the quarter. Factor I accounted for 60% of the variance at the beginning and 63U1o of the variance at the conclusion of the quarter. According to one researcher, the large eigenvalue and the percent of variance should identify Factor I as the evaluative dimension of community nutrition (12). The second factor accounted for 16.4U1o of the variance in the initial rating, and the scales with high correlation coefficients were those that described community nutrition as being reliable, realistic, visionary, orderly, and reassuring. In the rating at the conclusion of the quarter, the heavily loaded scales in Factor II had changed to pleasant, good, reliable, flexible, valuable, essential, and exciting and accounted for 1O.5U1o of the variance. Thus, at both the beginning and conclusion of the course, about 75U1o of the variance was explained by the two factors. Nutrition education. Table 2 involves ratings for the construct nutrition education. The correlation among scales made up of bipolar adjectives also differed over time. At the beginning of the quarter, nutrition education was viewed as pleasant, valuable, essential, significant, and exciting. At the conclusion of the quarter, the students viewed nutrition education as complete, July-September 1979
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Table 2 Scales indicating trends in attitudes toward nutrition education at beginning and conclusion of quarter
Scales Pleasant-unpleasant Complete-incomplete Up-to-date-behind-the-times Good-bad Reliable-unreliable Widespread-not prevalent Flexible-rigid Valuable-worthless Up-to-date-obsolete Essential-nonessential Visionary-shortsighted Powerful-weak Significant-insignificant Exciting-dull Orderly-chaotic Accessible-inaccessible Reassuring-frightening
Eigenvalues Variance
*
r~
Factor I Correlation Coefficient Pre (n: 188)
Post (n: 105)
Pre
Post
.408* .026 .024 .298 .210 .142 .117 .817* .169 .745* .100 .254 .430* .505* .048 .194 .150
.073 .455* .710* .587* .478* .108 .183 .306 .617* .051 .418* .170 .342 .348 .583* .248 .510*
.326 .084 .046 .324 .307 .272 .426* .160 .095 .130 .316 .532* .278 .312 .433* .515* .676*
.273 .356 .294 .068 .500* .627* .215 .033 .327 .131 .605* .577* .497* .329 .299 .533* .267
5.844 (Jl:.516
7.335 (Jl:.562
1.934 (Jl: .171
1.489 (Jl:.114
.40
up-to-date, good, reliable, vtSlonary, orderly, and reassuring. Instruction appeared to provide a framework in which a) current educational problems were identifiable (complete, up-to-date); b) sequencing for action was identified (orderly, visionary); and c) cognitive knowledge was applied toward problem solving (reliable, reassuring). The students may have used the words "pleasant" and "valuable" much like reading a good novel is pleasant or valuable. However, as future nutritionists, instruction seemed to result in attitudes which were oriented toward what nutrition education should be, i.e., up-to-date and complete. The evaluation factor (Factor I) explained 51.6070 of the variance at the beginning of the quarter as compared with 56.2070 of the variance following instruction. Factor II accounted for 17.1070 of the variance at the beginning, and 11.4070 of the variance at the conclusion. About 69070 of the variance was associated with Factors I and II; however, the evaluation factor is of primary importance in this study. In rating community nutrition and nutrition education, the power and the activity dimensions were not clearly shown. This can be explained on the basis that evaluative adjectives were selected purposefully and that a relatively homogeneous rating occurred postinstructional. Although correlation coefficients for the paired adjectives "powerful-weak" contributed significantly to Factor II, the other paired adjectives were more descriptive of an evaluative rather than a power dimension. The students responded primarily in evaluative terms, which was compatible with ideas that a semantic differential can provide affective evaluation of a community nutrition course.
Changes in Ratings Over Time Factor analyses provide information about inter-item correlations among the paired adjective scales. However, it does not identify the direction of change or proportion of change over time. In this study, it was important to examine the direction of change and significance of change in the ratings over time. Individuals' ratings were matched, using social security numbers and full completion of the S.D. forms. Any missing responses, inverted or missing digits, or multiple markings resulted in exclusion of that datum. As a result, 88 responses were exam130
Factor II Correlation Coefficient
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ined for proportion of change and the significance of change (Table 3). The direction of the change during the quarter is indicated by the appropriate plus or minus sign. The students perceived community nutrition as being more complete, up-todate, widespread, flexible, and orderly at the completion of the quarter. For each of these significant scales rated positively, the proportion of change was 60070 or greater. The frequency tables constructed for the McNemar tests provided the researchers with a type of item analysis that could prove to be valuable in future decisions about course content. Such examples are given in Figure 3 where responses to three scales on community nutrition are compared. The percentages associated with the valuable-worthless scale in Figure 3a show a low proportion of change as contrasted with the powerful-weak scale in Figure 3b, which indicated a widespread proportion of change. Neither of these scales showed sufficient differences in change of direction to be significant, according to McNemar's test, at the p~O.OOI level whereas in Figure 3c the proportion for the widespread-prevalent scale is highly significant at the p ~ .001 level. Forty-seven of the 88 respondents increased the rating toward "widespread," and only 15 students' ratings decreased toward "not prevalent" with 26 respondents showing no change. The scales that showed significant change when applied to nutrition education were pleasant-unpleasant, realisticidealistic, valuable-worthless, and significant-insignificant. It can be seen in Table 3 that the proportion and direction of change in the rating of the two constructs was similar, but the same scales were not significant for community nutrition and nutrition education.
Implications for Evaluation Strategies The overall purpose of this research was to utilize the semantic differential as a rating tool for evaluation purposes and to determine changes or trends in attitudes as a result of instruction. The findings indicate that pre- and postresponses to certain pairedadjective scales were statistically significant. For example, the scales with such descriptors as up-to-date, complete, widespread, and orderly were significant using factor analysis of McNemar's tests for proportion of change. This was not true for
(a)
(b)
Valuable-Worthless 5=0.353 (-) P=36.36
Powerful-Weak 5=1.133(+) P=71.59
N.S.
(e)
Widespread-Not Prevalent
N.S.
5=4.06 (+) P=70.45
p oS .001
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Figure 3 Percentage of students' responses on pre- and postratings for community nutrition. On the abscissa the intervals of the scales are recorded. On the ordinate the percentage responses from the cross tabulations are compared. The significance of change (5) was determined by McNemar's test and the proportion of change (P). *
= Number decreasing rating from pre to post N; = Number increasing rating from pre to post N no = Number with same response Nd
Table 3 Proportion and significance of change for pre- and postratings of community nutrition and nutrition education
Scales
Timely-untimely Pleasant-unpleasant Unusual-ordinary Advanced-elementary Complete-incomplete Up-to-date-behind-the-times Good-bad Reliable-unreliable Widespread-not prevalent Flexible-rigid Realistic-idealistic Valuable-worthless Fashionable-outmoded Up-to-date-obselete Labor-saving-wasteful Suitable-unsuitable Essential-nonessential Fast-slow Visionary-shortsighted Powerful-weak Significant-insignificant Exciting-dull Orderly-chaotic Accessible-inaccessible Reassuring-frightening • p:S.05
•• p:s .01
Community Nutrition (n = 88)
Nutrition Education (n = 91)
Significance of Change
Significance of Change
.142 (-) 1.408(-) .130(+) .516 (+) 3.812 (+)** 2.885 (+)** 1.021 (+) .420 (+) 4.066 (+)** 1.809 ( + ) .943 (-) .353 (-) .816 (+) 1.872 ( + ) .294 (+) .137 (+) .708 (-) .662 (-) .848 (+ +) 1.133 ( + ) .848 (-) 1.213 (-) 2.139 (+)* 1.152 (+) .674 (+)
Proportion of Change 55.68010 69.32 67.04 68.18 70.45 60.23 53.41 57.95 70.45 68.18 62.50 36.36 61.36 63.64 52.27 60.22 36.78 64.77 56.82 71.59 56.82 62.50 63.64 69.32 62.51
1.474 ( - ) 2.142 (-)* .534 (-) .124 (-) 1.116(+) .662 (-) 1.067 (+) .137 (+) 1.861 (+) .130 (+) 3.414 (-)** 3.413 (-)** 1.387 (+) .662 (-) .980 (-) 1.051 (-) 1.095 (-) .134 (+) .128(+) .816(-) 2.949 (-)** 1.664 (-) .384 (+) .911 (-) .911 (+)
Proportion of Change 50.55% 53.80 61.54 71.40 71.43 62.64 47.25 58.24 71.43 64.84 63.74 34.06 57.14 62.64 56.67 63.74 32.96 60.44 67.03 59.34 50.55 67.03 67.03 64.83 64.83
••• p:s .001
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a number of other scales because of the criteria set by the investigators. It is important to emphasize that the correlation coefficient required for inclusion of scales in the factor analysis, r = 0.40 as being significant, may be unnecessarily high. In truth, for the pre-instruction responses (n = 188), a correlation coefficient of r ~ 0.20 is statistically significant at p $ .01. Therefore, if a coefficient of r ~ 0.20 were acceptable to the investigators, many more paired-adjective scales could be considered as significant descriptors of both constructs, i.e., community nutrition and nutrition education. However, it is well recognized that response fatigue sets in when individuals are required to complete extensive rating scales. Therefore, selecting fewer scales is desirable. The findings also demonstrate that the selection of scales for a postevaluation tool should include all statistically significant scales which explain most of the variance and contribute to the unidimensionality of the scales. For community nutrition, 12 scales with evaluative descriptors had coefficients of r ~ 0.40 on Factor 1 (posttest) whereas nutrition education had eight scales on Factor I (posttest) meeting the criterion and reflecting an evaluative dimension. It is preferable to use fewer scales when most of the variance can be accounted for rather than to adminster the 25 scales consisting of bipolar adjectives. In terms of applied findings, a major component of this study involves an analysis of directional change for attitudes. Correlation coefficients indicate whether or not a change is significant, but do not provide the teacher with information about the positive or negative aspects of that change. As shown in Table 3 and Figure 3, the direction, proportion, and significance of change was determined by applying McNemar's test. Cross tabulations provided frequencies of numbers of students increasing, decreasing, or not changing the marking of each scale. This type of analysis has applications for course development and implementation because a series of evaluations over several quarters and/or years could form a basis for comparison. Modification in course content, teaching methods, and/or variations, when different teachers are assigned to a course, are likely to be reflected in students' attitudes toward that course, such as upto-date, complete, and widespread. It is recommended, therefore, that responses be analyzed for changes over time, indicating that attitudes have changed and what the direction of that change is. In summary, students increased the marking significantly on a number of scales on the construct of community nutrition. As a result of instruction, students' viewpoints toward the constructs of community nutrition and nutrition education were changed. 0
Acknowledgment This project was partially supported by the University of Minnesota Computer Center, Minneapolis, MN 55455.
References I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
17 18 19 20 21
Note This article is Scientific Journal Series No. 10,395, University of Minnesota Agricultural Experiment Station.
S!PJ€ r:Publications
22
Position paper on the scope and thrust of nutrition education, J. Am. Dietel. Assn., 72:302, 1978. Bloom, B. S., Human Characteristics and School Learning, McGraw-Hill, New York, 1976. Schwartz, N. E., and S. Barr, Mothers- Their attitudes and practices in perinatal nutrition, J. Nutr. Ed., 9:169, 1977. Bowering, J. et aI., Influence of a nutrition education program on infant nutrition in East Harlem, J. Am. Dietel. Assn., 72:393, 1978. Schutz, H. G., S. M. Moore, and M. H. Rucker, Predicting food purchase and use by multivariate attitudinal analysis, Food Tech., 31:568, 1977. Krause, T. 0., and H. M. Fox, Nutrition knowledge and attitudes of physicians, J. Am. Dietel. Assn., 70:607, 1977. Grotkowski, M. L., and L. S. Sims, Nutritional knowledge, attitudes and dietary practices of the elderly, J. Am. Dietel. Assn., 72:499, 1978. Carruth, B. R., and H. L. Anderson, Scaling criteria in developing and evaluating an attitude instrument, J. Am. Dietel. Assn., 70:42, 1977. Snider, J. G., and C. E. Osgood, Semantic Differential Technique, Aldine Publishing Co., Chicago, 1969. Cook, S. W., and C. Selltiz, A multiple indicator-approach to attitude measurement, Psych. Bull., 62:36, 1964. Shaw, M. E., and J. M. Wright, Scales for the measurement ofattitudes, McGraw-Hill, New York, 1967, pp. 1-32. Osgood, C. E., G. J. Suci, and P. H. Tanenbaum, The Measurement of Meaning, University of Illinois Press, Urbana, 1965, pp. 76-216. Brinton, J. E., Deriving an attitude scale from semantic differential data, Public Opinion QuarL, 25:289, 1961. McDowell, E. E., The semantic differential as a method of teacher evaluation, J. Ed. Res., 68:330, 1975. White, W. F., and M. de la Serna, Students' ratings of their instructors and the instructors' ratings of students in educational psychology, J. Psych., 92: 195, 1976. Nowacek, G. A., Validation of the Semantic Differential as a Measure of One Element of Affective Education: Attitude toward school subjects, Ph.D. dissertation, University of Michigan, Ann Arbor, 1976. Simpson, R. D., Assessing student behavior in the affective domain, Eng. Ed., 68:397, 1978. Sywak, M., A Study of Involvement and Consensus in Graduate Professional Library Education Using the Semantic Differential, Ph.D. dissertation, New York University, New York, 1977. Schutz, R. W., and F. L. Smoll, Equivalence of two inventories for assessing attitudes toward physical activity, Psych. Rep., 40: 1031, 1977. Summers, G. F., Attitude Measurement, Rand McNally & Co., Chicago, 1970, pp. 235-253. Nie, N. H. et aI., Statistical Package for the Social Sciences, 2d ed., McGraw-Hill, New York, 1975, pp. 468-514. Conover, W. L, Practical Nonparametric Statistics, John Wiley & Sons, New York, 1971, pp. 127-130.
ELEMENTARY
Approximately 225 printed and audiovisual materials are included in this updated resource. Those involved in teaching nutrition to elementary level students will find the selected materials useful as teaching tools and informational references. Entries for materials produced after 1974 are annotated with JNE review references cited. Titles and Spanish language items are indexed separately. Before October 1, 1979 $4.00
TEACHING MATERIALS
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AND
TEACHER REFERENCES
::R.evised