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Relationships between Growth need Strength and selected individual differences measures employed in job design research
Journal of Vocational
Behavior
14, 329-340 (1979)
Relationships between Growth Need Strength Selected Individual Differences Measures Employed in Job Design Research
and
EUGENE F. STONE, DANIEL C. GANSTER, RICHARD W. WOODMAN, AND MARCELLINE R. FUSILIER Purdue University The present study examines the degree to which the Growth Need Strength scales (Job Choice and Would Like formats) of the Job Diagnostic Survey (Hackman & Oldham, Journal of Applied Psychology, 1975,60, 159-170) correlate with (a) other measures of needs and values employed in research as moderators of the job scope-job satisfaction relationship and (b) a measure of social desirability. Results showed (a) only moderate correlations between the Growth Need Strength scales and the other measures of needs and values and (b) a relatively high degree of correlation between social desirability and the Would Like measure of Growth Need Strength. Implications of these findings for job design research are considered.
In a number of recent publications it has been argued that one or more individual differences variables moderate the relationship between job characteristics and affective reactions to jobs (cf., for example, Hackman & Lawler, 1971; Hackman & Oldham, 1975, 1976; Hulin, 1971; Hulin & Blood, 1968). Among the individual differences variables that have been used in previous task design research and theory are Growth Need Strength (e.g., Hackman & Oldham, 1975), Higher-Order Need Strength (e.g., Hackman & Lawler, 1971), rural vs urban residence or socialization (e.g., Schuler, 1973; Turner & Lawrence, 1965; Wanous, 1974), subscription to Protestant Ethic values (e.g., Stone, 1975, 1976), and needs for achievement and autonomy (e.g., Stone, Mowday, & Porter, 1977). Operationalizations of these constructs are of two basic types. The first Requests for reprints should be sent to Eugene F. Stone, Department of Administrative Sciences, Krannert Building, Purdue University, West Lafeyette, IN 47907. The research reported here was funded by a contract from the Office of Naval Research (NOOOl4-76-C-0164 NR 170-812). The authors express their gratitude to Richard T. Mowday for his assistance in various phases of this research. 329
OOOI-8791/79/030329-12$02.0010 Copyright @ 1979 by Academic Press, Inc. All rights of reproduction in any form reserved.
330
STONE ET AL.
type consists of self-report measures that index the level of particular characteristics (e.g.. variety and autonomy) individuals would like to have on their present jobs or on “ideal” jobs. Examples are the Higher-Order Need Strength measure of Hackman and Lawler (1971) and the Growth Need Strength measures (Job Choice and Would Like scales) of Hackman and Oldham (1975). These and similar instruments use individuals’ stated preferences for levels of various job characteristics as a basis for inferring the existence and strength of higher-order needs believed to be of import vis-a-vis relationships between task characteristics and affective and behavioral responses to jobs. The second group of instruments assess individual differences through self-report measures that make no specific reference to any given job and/or its characteristics. Examples are the work-related values (e.g., Pride in Work and Job Involvement) assessed by the Survey of Work Values (Wollack, Goodale, Wijting, & Smith, 1971) and the needs (e.g., Achievement and Autonomy) indexed by the Personality Research Form (Jackson, 1967). The research literature reveals that, in general, studies attempting to moderate relationships between job characteristics and responses to jobs have generally been “successful” when individual differences are measured by Growth Need Strength or Higher-Order Need Strength measures and “unsuccessful” when other types of measures are employed. One possible explanation for inconsistencies among these findings is that the underlying construct(s) indexed by the former types of measures may not share much variance with measures of the latter type. This rationale was, for example, invoked by Stone ef al. (1977) as a possible explanation of their finding that higher-order needs as measured by the needs for Achievement and Autonomy scales of the Personality Research Form did not strongly moderate the relationship between job scope and satisfaction with the work itself; a finding inconsistent with research in which higherorder needs have been measured with scales that tap individuals’ preferences for job characteristics (e.g.. Growth Need Strength and HigherOrder Need Strength). A review of the existing literature reveals only one study dealing with the issue of how higher-order needs as measured by the Hackman and Oldham (1975) Growth Need Strength scales correlate with other operationalizations of higher-order needs and measures of work-related values (see Aldag & Brief, 1977). In the study by Aldag and Brief, an attempt was made to demonstrate the reliability and validity of the Job Choice version of the Growth Need Strength measure. (Note that the Job Choice and Would Like measures of Growth Need Strength are considered to be alternative operationalizations of the same construct [cf.. for example, Hackman & Oldham, 1975, pp. 162-1631. See the Method section of the present paper for more information on the two measures.)
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Aldag and Brief reasoned that the Job Choice measure of Growth Need Strength should correlate positively with other measures of higher-order needs (e.g., needs for Occupational Achievement and Self Actualization as measured by Ghiselli’s, 1971, Self Description Inventory) and with a measure of adherence to the Protestant Ethic (Blood’s, 1969, measure). Data from the study were obtained from five different groups (i.e., nursing aides, correctional employees, manufacturing operatives, hospital employees. and police officers). Results of the study showed that Job Choice correlated positively with needs for both Occupational Achievement and Self Actualization. The correlations ranged from .I40 to .344 in the two samples for which there were data. In addition, Job Choice correlated positively with Protestant Ethic. These latter correlations ranged from .162 to .290 in the three samples for which data were available. Aldag and Brief interpreted these results as showing support for the convergent validity of the Job Choice measure of Growth Need Strength. While the Aldag and Brief study shows modest correlations between the Job Choice measure of Growth Need Strength and other measures of job-related needs and values it does not provide direct et’idence on the degree to which either the Job Choice or the Would Like measures of Growth Need Strength correlate with selected other measures that have been employed in job design research. More specifically, the Aldag and Brief research provides no evidence on how the Job Choice and Would Like Growth Need Strength scales correlate with the various subscales of the Protestant Ethic index developed by Wollack er nl. ( 1971)or the needs for achievement, autonomy, etc., measured by the subscales of the Personality Research Form (Jackson, 1967). Evidence on these relationships would appear valuable since, as mentioned earlier, research employing the Job Choice and/or Would Like measures of Growth Need Strength has. in general, shown moderating effects, while research employing the Wollack et al. (1971) measure (e.g.. Stone, 1975. 1976) or needs measured by the Personality Research Form (e.g.. Stone et al., 1977) has, in general, failed to show such effects. The purpose of the present study, therefore, was to examine the extent to which the Job Choice and Would Like measures of Growth Need Strength correlate with measures of adherence to the Protestant Ethic (as indexed by the Survey of Work Values measure) and selected measures of higher order needs (as indexed by the Personality Research Form). Arguments advanced in the extant literature (e.g., Aldag & Brief, 1977; Brief & Aldag. 1975: Hackman & Lawler, 1971; Stone, 1974. 1975, 1976; Stone et al., 1977; Wanous, 1974) lead to the hypothesis that scores on the Job Choice and Would Like measures of Growth Need Strength will correlate positively with (a) the needs for Achievement, Autonomy, Change. and Endurance as measured by the Personality Research Form, and (b) the values of Activity Preference, Upward Striving, Social Status
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of the Job, Attitude Toward Earnings, Pride in Work, and Job Involvement, as measured by the Survey of Work Values. In addition to assessing the strength of the above mentioned relationships, the present study also examines the extent to which the Job Choice and Would Like measures of Growth Need Strength correlate with a measure of social desirability response bias (i.e., the Social Desirability scale of the Personality Research Form). To the extent that these measures of Growth Need Strength correlate with Social Desirability their validity is called into question. METHOD Subjects
Data for the present study were obtained from 133 undergraduate students in an introductory organizational behavior course at a large midwestern university. The average age of study participants was 20.7 years (s = 1.2). The sample contained 102 males and 31 females. Most students in the class (i.e., about 80%) were management majors. Participation in the study was voluntary. As an inducement to participate, however, students were offered a small amount of extra credit toward their course grade. The same amount of credit was available to nonparticipants for involvement in or completion of other research and/or nonresearch projects. Procedure
As part of a larger study, each subject was requested to attend two group testing sessions. In the first session subjects completed the Personality Research Form (Jackson, 1967). One week after this, subjects completed (a) the Job Choice and Would Like measures of Growth Need Strength and (b) the Survey of Work Values. Personality Research Form. The Personality Research Form is a nonclinical instrument for the assessment of personality. It contains 440 true-false items and has subscales aimed at assessing needs for Abasement, Achievement, Affiliation, Aggression, Autonomy, Change, Cognitive Structure, Defendence, Dominance, Endurance, Exhibition, Harmavoidance, Impulsivity, Nurturance, Order, Play, Sentience, Social Recognition, Succorance, and Understanding. In addition, there are scales to measure random responding (Infrequency scale) and responding motivated by the desire to present the self in a socially desirable manner (Social Desirability scale). Reliability and validity estimates are reported in Jackson (1967). Growth Need Strength. The Job Choice and Would Like measures of Growth Need Strength developed by Hackman and Oldham (1975) were used in the present study. The Would Like scale is composed of 11 items
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(only six of which are used for scoring) which ask respondents to indicate the degree to which they would like to have certain conditions present in their jobs (e.g., “the feeling of worthwhile accomplishment I get from doing my job”). The Job Choice scale, on the other hand, consists of 12 items which elicit relative preferences between two jobs that differ in terms of their potential for providing growth need satisfaction (e.g., “A job where you are often required to make important decisions” vs “A job with many pleasant people to work with”). Hackman and Oldham (1975) report internal consistency reliabilities of .88 for the Would Like scale and .71 for the Job Choice scale, and a between scale of correlation of 50. Survey of Work Values. The Survey of Work Values consists of 54 items with 5-point agree-disagree response possibilities. Included are scales for assessing the work related values of Social Status of the Job, Activity Preference. Upward Striving, Attitude Toward Earnings, Pride in Work, and Job Involvement. Each scale consists of 9 items. Reliability and validity information for the Survey of Work Values are given in Wollack et al. (1971). RESULTS Psychometric
Properties
of Measures
Internal consistency reliabilities of measures used in the present study are presented in the first column of Table I. Reliability coefficients (KR20) for scales of the Personality Research Form are those reported by Jackson (1967). Coefficient alphas (Cronbach, 1951) for the Growth Need Strength and Survey of Work Values scales were computed using data from the present study. The reliabilities of all scales but Attitude Towards Earnings are .57 or above, Note that reliability estimates for the Job Choice and Would Like Growth Need Strength Scales are similar to those reported by Hackman and Oldham (1975). Computed reliabilities for the Survey of Work Values scales are, however, generally higher than those reported by the instrument’s developers (Wollack er al., 1971). Table 1 also shows product-moment correlations between the individual differences measures of interest to the present study and the values of the same correlations corrected for attenuation due to unreliability (cf. Nunnally, 1967, p. 204). Relationships between Growth Need Strength Research Form Measures
Scales and Personality
Consistent with what had been hypothesized, the Job Choice measure of Growth Need Strength correlates significantly with needs for Achievement, Autonomy, Change, and Endurance. The observed correlations vary between .18 and .24. Corrected for attenuation due to unreliability, the correlations range from .25 to .34.
.6J .85
.62 .74 .68 .5J .82 .J9
.J8 .62
.60
.I2 .J4
Reliability of measure
.24**,”
that
.28
-
correlations
.21**
-
are statistically
.2J
-.Ol .06
-
.34b .26 .33 .25 .32
Format Corrected
-
r
r
Correlation Growth
Variables
-.I0 .Ol .l8* -.I0
.21**
.l8* .21** .l8*
I Studied
Job Choice
TABLE Between
Observed
R N = I33 for all correlation coefficients shown in the table. h Corrected correlation coefficients are shown only for observed * p < .os. ** p 4 .Ol.
Personality Research Form: Achievement Autonomy Change Endurance Social desirability Survey of Work Values: Social status of job Activity preference Upward striving Attitude toward earnings Pride in work Job involvement Growth Need Strength: Job choice Would like
Variables correlated with Growth Need Strength Scale scores
Relationships
significant
.3l
.26 .21**
at the alpha
.21** -
.30
.23** -.OJ .26**
.28 -
-
.I8
-
.20 .50
-
.38 -
Format Corrected
s .05 level.
Like
.14*
-.07
.36**
.l6*
r
Would
.30** -.OJ -.02
Observed
of variable with Need Strength r
c
2
mz
r? 0
INDIVIDUAL
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Also consistent with what had been hypothesized, the Would Like measure of Growth Need Strength correlates significantly with needs for Achievement and Endurance. The respective correlations are .30 and .16, which when corrected for unreliability increase to .38 and .20. The Would Like measure of Growth Need Strength, however, fails to correlate with the needs for Autonomy and Change. Overall the correlations show support for the hypothesized relationships between (a) the Job Choice and Would Like operationalizations of Growth Need Strength and (b) various needs measured by the Personality Research Form. The relationships, even when corrected for unreliability, however, are not very strong. Relationships between Growth Need Strength Scales and Surlley of Work Values Measures The hypothesized relationships between the Job Choice measure of Growth Need Strength and the scales of the Survey of Work Values were generally not found. The only scale of the Survey of Work Values that correlated with the Job Choice measure was Upward Striving: The observed and corrected correlations are, respectively, .18 and .27. There was modest support for the hypothesized relationships between the Would Like measure of Growth Need Strength and the scales of the Survey of Work Values. Four of the six observed correlations were significant. These ranged between . I4 and .26. Corrected for unreliability the same four correlations ranged from . I8 to .3l. Other Relationships of interest Three other correlations found in the present study are worthy of note. One is the relationship found between the Job Choice and the Would Like measures of Growth Need Strength. The observed correlation between these two measures is 21, which when corrected for unreliability increases to 28. A second is the correlation between the Job Choice measure and Social Desirability. The observed and corrected correlations are, respectively, .?I and .32. The results indicate that Social Desirability correlates at least as strongly with the Job Choice measure of Growth Need Strength as do the four needs measured by the Personality Research Form or the six values indexed by the Survey of Work Values. The third and final correlation that merits attention is that between the Would Like measure of Growth Need Strength and Social Desirability. The observed correlation is .36, which when corrected for unreliability increases to .50. The findings show that Social Desirability is a stronger correlate of the Would Like measure than any of the four needs or six values measured in the present study.
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DISCUSSION The major purpose of the present study was to assess the degree to which the Job Choice and Would Like measures of Growth Need Strength share variance with measures of several other individual differences variables employed in job design research. A secondary purpose was to determine the extent to which these alternative operationalizations of Growth Need Strength correlate with a measure of social desirability. Results associated with these two study objectives are discussed in turn. Needs Measured by the Personality Research Form The present study detected only moderate correlations between (a) the two measures of Growth Need Strength and (b) the four needs measured by the Personality Research Form. Even when the observed correlations were corrected for attenuation due to unreliability, the results revealed only modest convergence between members of these two sets of individual differences measures: The largest corrected correlation (i.e., that between Would Like and need for Achievement) is .38. indicating that the two measures share only 14.4% common variance. These results may serve to explain why attempts to moderate the job scope-job satisfaction relationship with Growth Need Strength measures (e.g., Hackman & Oldham, 1976; Umstot, Bell, & Mitchell, 1976) have produced findings inconsistent with attempts to moderate the same relationship using Personality Research Form measures of needs for Achievement and Autonomy (e.g.. Stone et al.. 1977). Interestingly, the two measures of Growth Need Strength show slightly different patterns of correlations with needs measured by the Personality Research Form. More specifically, while the needs for Autonomy and Change correlate significantly with the Job Choice measure, they are uncorrelated with the Would Like measure. These results suggest that the two measures of Growth Need Strength map not be measuring the same underlying construct. This observation is bolstered by the fact that the observed and corrected correlations between these two measures of Growth Need Strength are only 21 and .28, respectively. A comparison of the present study’s results with those of Aldag and Brief (1977) shows that the Job Choice measure of Growth Need Strength (common to both studies) has correlations of approximately the same magnitude with other measures of higher order needs. In the Aldag and Brief study, for example, the Job Choice measure correlated .344 and .349, respectively, with needs for Occupational Achievement and SelfActualization (police officer sample). In the present study the Job Choice measure showed a (corrected) correlation of .34 with the need for Achievement. (Note that in the present study the Would Like measure correlated .38 with the same need.) Taken together, the results of the
INDIVIDUAL
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present study and that of Aldag and Brief show only a low degree of convergence between the Growth Need Strength measures and other measures of higher order needs. Values Measured
by the Survey of Work Values
The present study’s results revealed only slight convergence between the two measures of Growth Need Strength and the values assessed by the Survey of Work Values. Only one of the six values was found to correlate significantly with the Job Choice measure of Growth Need Strength. The observed correlation was, however, quite low (i.e., .18). And, while four of the six measures of work-related values were found to correlate significantly with the Would Like measure of Growth Need Strength, the largest of the observed correlations was only .26 (which when corrected increased to .3l). These results may serve to explain inconsistencies in the outcomes of previous research employing work values measures (e.g., Stone, 1975, 1976) as opposed to Higher Order Need Strength or Growth Need Strength measures (e.g., Hackman & Lawler, 1971; Hackman & Oldham, 1976) as moderators of relationships between job characteristics and individuals’ affective responses to jobs. Moreover, the results suggest that there may be only slight conceptual similarity between the individual differences moderators mentioned in such works as Hulin and Blood (1968), Hulin (1971), and Stone (1975, 1976), and those discussed in such works as Hackman and Lawler (1971) and Hackman and Oldham (1975, 1976). Similar to the findings associated with needs measured by the Personality Research Form, the Job Choice and Would Like measures of Growth Need Strength show generally dissimilar patterns of correlations with values indexed by the Survey of Work Values. The only work value that correlates significantly with both the Job Choice and Would Like measures is Upward Striving. Again, what is suggested is that the two measures of Growth Need Strength may not be representative of the same content domain. Research by Aldag and Brief (1977) revealed correlations between the Job Choice measure and Blood’s (1969) Protestant Ethic measure that ranged between .162 (hospital employee sample) and .290 (police officer sample). In the present study the Job Choice measure had a (corrected) correlation of .27 with the Upward Striving subscale of the Survey of Work Values. (The largest correlation for the Would Like measure, on the other hand, was .31 and involved the Pride in Work subscale.) Results of the present study and that of Aldag and Brief show a relatively low degree of convergence between Protestant Ethic values (either the measures of Blood or Wollack et al.) and scores produced by the Growth Need Strength scales.
338
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AL.
Zn$uence of Social Desirability Data from the present study revealed that both the Job Choice and the Would Like measures of Growth Need Strength are contaminated with social desirability response bias. In the case of the Job Choice measure the observed and corrected correlations are, respectively, .2l and .32. The corrected correlation suggests that Social Desirability accounts for only 10.2% of the variance in Job Choice scores. In the case of the Would Like measure of Growth Need Strength. however, the results are more damaging. The observed and corrected correlations between Social Desirability and the Would Like measure of Growth Need Strength are .36 and .50, respectively. The latter correlation suggesting that 25% of the variance in the Would Like measure can be accounted for by Social Desirability. The present study’s social desirability related results point to the need for further developmental work on the Growth Need Strength measures prior to their continued use in either basic or applied research. This need is obviously more critical in the case of the Would Like measure than it is in the case of the Job Choice measure. SUMMARY AND CONCLUSIONS Results of the present study, in sumnary form, are as follows: (a) There appears to be little convergence between the constructs indexed by the Would Like and Job Choice measures of Growth Need Strength; (b) needs measured by the Personality Research Form show modest and inconsistent relationships with the two Growth Need Strength measures: (c) values measured by the Survey of Work Values reveal generally low and inconsistent relationships with the Growth Need Strength measures; and (d) responses to both the Job Choice and Would Like measures of Growth Need Strength are contaminated by social desirability response bias. Three conclusions and/or recommendations appear warranted on the basis of these findings. First, results of research employing either of the two Growth Need Strength scales (or the earlier Higher-Order Need Strength measure of Hackman & Lawler. 1971) cannot be directly compared with the results of research employing measures of needs for Achievement, Autonomy, etc., and such work-related values as Job Involvement, Pride in Work, and Upward Striving. Growth Need Strength appears to share only modest proportions of variance with these other measures of individual differences. Second, given the relatively low degree of convergence between Growth Need Strength scale scores and other needs and values detected in the present study and that of Aldag and Brief (1977), consideration should be given to changing the label attached to scores produced by the Job Choice and Would Like measures. It would appear that these
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two measures index a person’s “preferences for degrees of job enrichment”-not a person’s general need for psychological growth. While it might be argued that “preferences for degrees ofjob enrichment” should be related to “needs for psychological growth,” it would appear unwarranted to assert that these constructs are equivalent. It would, therefore, seem reasonable to suggest that rather than referring to scores produced by the Job Choice and Would Like scales as indices of Growth Need Strength, instead they should be referred to as indices of Preferences for Job Scope or Desires for Enriched Work. Third, it would appear that additional development of the Growth Need Strength scales is needed. A major reason for this is the lack of convergence between the Job Choice and Would Like measures of Growth Need Strength. Corrected for unreliability the two measures correlate only .28 with one another (indicating that they share only 7.8% common variance). Another reason for recommending further developmental work on these scales is the social desirability-related findings. The 25% shared variability between Social Desirability and the Would Like measure is particularly disturbing. A final reason for recommending more research is that little is presently known about the construct (especially convergent and discriminant) validity of the Growth Need Strength measures. It is hoped that the results of the present study will serve as an impetus for such additional research. REFERENCES Aldag, R. J., & Brief, A. P. Examination of a meaure of higher order need strength. In 0. Behling & J. C. Henderson (Eds.), Proceedings ofthe 20th annual conference: Midwest Acudemy of Management. Columbus: Ohio State University, 1977. Blood. M. R. Work values and job satisfaction. Journul of Applied Psychology. 1969, 53, 456-459. Brief, A. P., & Aldag. R. J. Employee reactions to job characteristics: A constructive replication. Journal of Applied Psychology, 1975, 60, 182-186. Cronbach, L. J. Coefficient alpha and the internal structure of tests. Psychometrika. I95 I, 16, 297-334. Ghiselli, E. E. Explorations in mnnagerial talent. Pacific Palisades. Ca.: Goodyear Publishing Co.. 1971. Hackman. J. R., & Lawler, E. E. Employee reactions to job characteristics. Journal of Applied Psychology, 1971, 55, 259-286. Hackman, J. R., & Oldham. G. R. Development of the job diagnostic survey. Journal of Applied Psychology, 1975, 60, 159-170. Hackman, J. R., & Oldham, G. R. Motivation through the design of work: Test of a theory. Orgunizutionul Behuvior and Human Performance, 1976, 16, 250279. Hulin, C. L. Individual differences and job enrichment. In J. R. Maher (Ed.), New perspectives in job enrichment. New York: Van Nostrand-Reinhold, 1971. Hulin, C. L., & Blood, M. R. Job enlargement. individual differences. and worker responses. Psychological Bulletin, 1968, 69, 41-55. Jackson. D. N. Personality Reseurch Form mum&. Goshen, N.Y.: Research Psychologists Press. 1967.
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Nunnally, J. C. Psychomerric theory. New York: McGraw-Hill, 1967. Schuler, R. Worker background and job satisfaction. Industrial and Labor Relations Review, 1973, 26, 851-853. Stone, E. F. The moderating effect of work-related values on the job scope-job satisfaction relationship. (Doctoral Dissertation, University of California, Irvine, 1974) Dissertation Absrracrs International, 1974, 35, 3082B. (University Microfilms No. 74-27. 381) Stone. E. F. Job scope, job satisfaction, and the Protestant ethic: A study of enlisted men in the U.S. Navy. Journal of Vocational Behavior, 1975. 7, 215-224. Stone, E. F. The moderating effect of work-related values on the job scope-job satisfaction relationship. Organizational Behavior and Human Performance, 1976. 15, 147-167. Stone, E. F., Mowday. R. T., & Porter, L. W. Higher order need strengths as moderators of the job scope-job satisfaction relationship. Journal of Applied Psychology, 1977. 62, 466-471. Turner, A. N., & Lawrence, P. R. Industrial jobs and rhe worker. Boston: Harvard University Press, 1965. Umstot, D. D., Bell, C. H.. & Mitchell, T. R. Effects ofjob enrichment and task goals on satisfaction and productivity: Implications for job design. Journal of Applied Psycho/ogy, 1976, 61, 379-394. Wanous, J. P. Individual differences and reactions to job characteristics. Journal ofApplied Psychology, 1974, 59, 616-622. Wollack, S., Goodale, J. G., Wijting. J. P.. & Smith, P. C. Development of the Survey of Work Values. Journal of Applied Psychology, 1971, 55, 331-338. Received:
August 7. 1978.
Behavior
14, 329-340 (1979)
Relationships between Growth Need Strength Selected Individual Differences Measures Employed in Job Design Research
and
EUGENE F. STONE, DANIEL C. GANSTER, RICHARD W. WOODMAN, AND MARCELLINE R. FUSILIER Purdue University The present study examines the degree to which the Growth Need Strength scales (Job Choice and Would Like formats) of the Job Diagnostic Survey (Hackman & Oldham, Journal of Applied Psychology, 1975,60, 159-170) correlate with (a) other measures of needs and values employed in research as moderators of the job scope-job satisfaction relationship and (b) a measure of social desirability. Results showed (a) only moderate correlations between the Growth Need Strength scales and the other measures of needs and values and (b) a relatively high degree of correlation between social desirability and the Would Like measure of Growth Need Strength. Implications of these findings for job design research are considered.
In a number of recent publications it has been argued that one or more individual differences variables moderate the relationship between job characteristics and affective reactions to jobs (cf., for example, Hackman & Lawler, 1971; Hackman & Oldham, 1975, 1976; Hulin, 1971; Hulin & Blood, 1968). Among the individual differences variables that have been used in previous task design research and theory are Growth Need Strength (e.g., Hackman & Oldham, 1975), Higher-Order Need Strength (e.g., Hackman & Lawler, 1971), rural vs urban residence or socialization (e.g., Schuler, 1973; Turner & Lawrence, 1965; Wanous, 1974), subscription to Protestant Ethic values (e.g., Stone, 1975, 1976), and needs for achievement and autonomy (e.g., Stone, Mowday, & Porter, 1977). Operationalizations of these constructs are of two basic types. The first Requests for reprints should be sent to Eugene F. Stone, Department of Administrative Sciences, Krannert Building, Purdue University, West Lafeyette, IN 47907. The research reported here was funded by a contract from the Office of Naval Research (NOOOl4-76-C-0164 NR 170-812). The authors express their gratitude to Richard T. Mowday for his assistance in various phases of this research. 329
OOOI-8791/79/030329-12$02.0010 Copyright @ 1979 by Academic Press, Inc. All rights of reproduction in any form reserved.
330
STONE ET AL.
type consists of self-report measures that index the level of particular characteristics (e.g.. variety and autonomy) individuals would like to have on their present jobs or on “ideal” jobs. Examples are the Higher-Order Need Strength measure of Hackman and Lawler (1971) and the Growth Need Strength measures (Job Choice and Would Like scales) of Hackman and Oldham (1975). These and similar instruments use individuals’ stated preferences for levels of various job characteristics as a basis for inferring the existence and strength of higher-order needs believed to be of import vis-a-vis relationships between task characteristics and affective and behavioral responses to jobs. The second group of instruments assess individual differences through self-report measures that make no specific reference to any given job and/or its characteristics. Examples are the work-related values (e.g., Pride in Work and Job Involvement) assessed by the Survey of Work Values (Wollack, Goodale, Wijting, & Smith, 1971) and the needs (e.g., Achievement and Autonomy) indexed by the Personality Research Form (Jackson, 1967). The research literature reveals that, in general, studies attempting to moderate relationships between job characteristics and responses to jobs have generally been “successful” when individual differences are measured by Growth Need Strength or Higher-Order Need Strength measures and “unsuccessful” when other types of measures are employed. One possible explanation for inconsistencies among these findings is that the underlying construct(s) indexed by the former types of measures may not share much variance with measures of the latter type. This rationale was, for example, invoked by Stone ef al. (1977) as a possible explanation of their finding that higher-order needs as measured by the needs for Achievement and Autonomy scales of the Personality Research Form did not strongly moderate the relationship between job scope and satisfaction with the work itself; a finding inconsistent with research in which higherorder needs have been measured with scales that tap individuals’ preferences for job characteristics (e.g.. Growth Need Strength and HigherOrder Need Strength). A review of the existing literature reveals only one study dealing with the issue of how higher-order needs as measured by the Hackman and Oldham (1975) Growth Need Strength scales correlate with other operationalizations of higher-order needs and measures of work-related values (see Aldag & Brief, 1977). In the study by Aldag and Brief, an attempt was made to demonstrate the reliability and validity of the Job Choice version of the Growth Need Strength measure. (Note that the Job Choice and Would Like measures of Growth Need Strength are considered to be alternative operationalizations of the same construct [cf.. for example, Hackman & Oldham, 1975, pp. 162-1631. See the Method section of the present paper for more information on the two measures.)
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Aldag and Brief reasoned that the Job Choice measure of Growth Need Strength should correlate positively with other measures of higher-order needs (e.g., needs for Occupational Achievement and Self Actualization as measured by Ghiselli’s, 1971, Self Description Inventory) and with a measure of adherence to the Protestant Ethic (Blood’s, 1969, measure). Data from the study were obtained from five different groups (i.e., nursing aides, correctional employees, manufacturing operatives, hospital employees. and police officers). Results of the study showed that Job Choice correlated positively with needs for both Occupational Achievement and Self Actualization. The correlations ranged from .I40 to .344 in the two samples for which there were data. In addition, Job Choice correlated positively with Protestant Ethic. These latter correlations ranged from .162 to .290 in the three samples for which data were available. Aldag and Brief interpreted these results as showing support for the convergent validity of the Job Choice measure of Growth Need Strength. While the Aldag and Brief study shows modest correlations between the Job Choice measure of Growth Need Strength and other measures of job-related needs and values it does not provide direct et’idence on the degree to which either the Job Choice or the Would Like measures of Growth Need Strength correlate with selected other measures that have been employed in job design research. More specifically, the Aldag and Brief research provides no evidence on how the Job Choice and Would Like Growth Need Strength scales correlate with the various subscales of the Protestant Ethic index developed by Wollack er nl. ( 1971)or the needs for achievement, autonomy, etc., measured by the subscales of the Personality Research Form (Jackson, 1967). Evidence on these relationships would appear valuable since, as mentioned earlier, research employing the Job Choice and/or Would Like measures of Growth Need Strength has. in general, shown moderating effects, while research employing the Wollack et al. (1971) measure (e.g.. Stone, 1975. 1976) or needs measured by the Personality Research Form (e.g.. Stone et al., 1977) has, in general, failed to show such effects. The purpose of the present study, therefore, was to examine the extent to which the Job Choice and Would Like measures of Growth Need Strength correlate with measures of adherence to the Protestant Ethic (as indexed by the Survey of Work Values measure) and selected measures of higher order needs (as indexed by the Personality Research Form). Arguments advanced in the extant literature (e.g., Aldag & Brief, 1977; Brief & Aldag. 1975: Hackman & Lawler, 1971; Stone, 1974. 1975, 1976; Stone et al., 1977; Wanous, 1974) lead to the hypothesis that scores on the Job Choice and Would Like measures of Growth Need Strength will correlate positively with (a) the needs for Achievement, Autonomy, Change. and Endurance as measured by the Personality Research Form, and (b) the values of Activity Preference, Upward Striving, Social Status
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of the Job, Attitude Toward Earnings, Pride in Work, and Job Involvement, as measured by the Survey of Work Values. In addition to assessing the strength of the above mentioned relationships, the present study also examines the extent to which the Job Choice and Would Like measures of Growth Need Strength correlate with a measure of social desirability response bias (i.e., the Social Desirability scale of the Personality Research Form). To the extent that these measures of Growth Need Strength correlate with Social Desirability their validity is called into question. METHOD Subjects
Data for the present study were obtained from 133 undergraduate students in an introductory organizational behavior course at a large midwestern university. The average age of study participants was 20.7 years (s = 1.2). The sample contained 102 males and 31 females. Most students in the class (i.e., about 80%) were management majors. Participation in the study was voluntary. As an inducement to participate, however, students were offered a small amount of extra credit toward their course grade. The same amount of credit was available to nonparticipants for involvement in or completion of other research and/or nonresearch projects. Procedure
As part of a larger study, each subject was requested to attend two group testing sessions. In the first session subjects completed the Personality Research Form (Jackson, 1967). One week after this, subjects completed (a) the Job Choice and Would Like measures of Growth Need Strength and (b) the Survey of Work Values. Personality Research Form. The Personality Research Form is a nonclinical instrument for the assessment of personality. It contains 440 true-false items and has subscales aimed at assessing needs for Abasement, Achievement, Affiliation, Aggression, Autonomy, Change, Cognitive Structure, Defendence, Dominance, Endurance, Exhibition, Harmavoidance, Impulsivity, Nurturance, Order, Play, Sentience, Social Recognition, Succorance, and Understanding. In addition, there are scales to measure random responding (Infrequency scale) and responding motivated by the desire to present the self in a socially desirable manner (Social Desirability scale). Reliability and validity estimates are reported in Jackson (1967). Growth Need Strength. The Job Choice and Would Like measures of Growth Need Strength developed by Hackman and Oldham (1975) were used in the present study. The Would Like scale is composed of 11 items
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(only six of which are used for scoring) which ask respondents to indicate the degree to which they would like to have certain conditions present in their jobs (e.g., “the feeling of worthwhile accomplishment I get from doing my job”). The Job Choice scale, on the other hand, consists of 12 items which elicit relative preferences between two jobs that differ in terms of their potential for providing growth need satisfaction (e.g., “A job where you are often required to make important decisions” vs “A job with many pleasant people to work with”). Hackman and Oldham (1975) report internal consistency reliabilities of .88 for the Would Like scale and .71 for the Job Choice scale, and a between scale of correlation of 50. Survey of Work Values. The Survey of Work Values consists of 54 items with 5-point agree-disagree response possibilities. Included are scales for assessing the work related values of Social Status of the Job, Activity Preference. Upward Striving, Attitude Toward Earnings, Pride in Work, and Job Involvement. Each scale consists of 9 items. Reliability and validity information for the Survey of Work Values are given in Wollack et al. (1971). RESULTS Psychometric
Properties
of Measures
Internal consistency reliabilities of measures used in the present study are presented in the first column of Table I. Reliability coefficients (KR20) for scales of the Personality Research Form are those reported by Jackson (1967). Coefficient alphas (Cronbach, 1951) for the Growth Need Strength and Survey of Work Values scales were computed using data from the present study. The reliabilities of all scales but Attitude Towards Earnings are .57 or above, Note that reliability estimates for the Job Choice and Would Like Growth Need Strength Scales are similar to those reported by Hackman and Oldham (1975). Computed reliabilities for the Survey of Work Values scales are, however, generally higher than those reported by the instrument’s developers (Wollack er al., 1971). Table 1 also shows product-moment correlations between the individual differences measures of interest to the present study and the values of the same correlations corrected for attenuation due to unreliability (cf. Nunnally, 1967, p. 204). Relationships between Growth Need Strength Research Form Measures
Scales and Personality
Consistent with what had been hypothesized, the Job Choice measure of Growth Need Strength correlates significantly with needs for Achievement, Autonomy, Change, and Endurance. The observed correlations vary between .18 and .24. Corrected for attenuation due to unreliability, the correlations range from .25 to .34.
.6J .85
.62 .74 .68 .5J .82 .J9
.J8 .62
.60
.I2 .J4
Reliability of measure
.24**,”
that
.28
-
correlations
.21**
-
are statistically
.2J
-.Ol .06
-
.34b .26 .33 .25 .32
Format Corrected
-
r
r
Correlation Growth
Variables
-.I0 .Ol .l8* -.I0
.21**
.l8* .21** .l8*
I Studied
Job Choice
TABLE Between
Observed
R N = I33 for all correlation coefficients shown in the table. h Corrected correlation coefficients are shown only for observed * p < .os. ** p 4 .Ol.
Personality Research Form: Achievement Autonomy Change Endurance Social desirability Survey of Work Values: Social status of job Activity preference Upward striving Attitude toward earnings Pride in work Job involvement Growth Need Strength: Job choice Would like
Variables correlated with Growth Need Strength Scale scores
Relationships
significant
.3l
.26 .21**
at the alpha
.21** -
.30
.23** -.OJ .26**
.28 -
-
.I8
-
.20 .50
-
.38 -
Format Corrected
s .05 level.
Like
.14*
-.07
.36**
.l6*
r
Would
.30** -.OJ -.02
Observed
of variable with Need Strength r
c
2
mz
r? 0
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Also consistent with what had been hypothesized, the Would Like measure of Growth Need Strength correlates significantly with needs for Achievement and Endurance. The respective correlations are .30 and .16, which when corrected for unreliability increase to .38 and .20. The Would Like measure of Growth Need Strength, however, fails to correlate with the needs for Autonomy and Change. Overall the correlations show support for the hypothesized relationships between (a) the Job Choice and Would Like operationalizations of Growth Need Strength and (b) various needs measured by the Personality Research Form. The relationships, even when corrected for unreliability, however, are not very strong. Relationships between Growth Need Strength Scales and Surlley of Work Values Measures The hypothesized relationships between the Job Choice measure of Growth Need Strength and the scales of the Survey of Work Values were generally not found. The only scale of the Survey of Work Values that correlated with the Job Choice measure was Upward Striving: The observed and corrected correlations are, respectively, .18 and .27. There was modest support for the hypothesized relationships between the Would Like measure of Growth Need Strength and the scales of the Survey of Work Values. Four of the six observed correlations were significant. These ranged between . I4 and .26. Corrected for unreliability the same four correlations ranged from . I8 to .3l. Other Relationships of interest Three other correlations found in the present study are worthy of note. One is the relationship found between the Job Choice and the Would Like measures of Growth Need Strength. The observed correlation between these two measures is 21, which when corrected for unreliability increases to 28. A second is the correlation between the Job Choice measure and Social Desirability. The observed and corrected correlations are, respectively, .?I and .32. The results indicate that Social Desirability correlates at least as strongly with the Job Choice measure of Growth Need Strength as do the four needs measured by the Personality Research Form or the six values indexed by the Survey of Work Values. The third and final correlation that merits attention is that between the Would Like measure of Growth Need Strength and Social Desirability. The observed correlation is .36, which when corrected for unreliability increases to .50. The findings show that Social Desirability is a stronger correlate of the Would Like measure than any of the four needs or six values measured in the present study.
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DISCUSSION The major purpose of the present study was to assess the degree to which the Job Choice and Would Like measures of Growth Need Strength share variance with measures of several other individual differences variables employed in job design research. A secondary purpose was to determine the extent to which these alternative operationalizations of Growth Need Strength correlate with a measure of social desirability. Results associated with these two study objectives are discussed in turn. Needs Measured by the Personality Research Form The present study detected only moderate correlations between (a) the two measures of Growth Need Strength and (b) the four needs measured by the Personality Research Form. Even when the observed correlations were corrected for attenuation due to unreliability, the results revealed only modest convergence between members of these two sets of individual differences measures: The largest corrected correlation (i.e., that between Would Like and need for Achievement) is .38. indicating that the two measures share only 14.4% common variance. These results may serve to explain why attempts to moderate the job scope-job satisfaction relationship with Growth Need Strength measures (e.g., Hackman & Oldham, 1976; Umstot, Bell, & Mitchell, 1976) have produced findings inconsistent with attempts to moderate the same relationship using Personality Research Form measures of needs for Achievement and Autonomy (e.g.. Stone et al.. 1977). Interestingly, the two measures of Growth Need Strength show slightly different patterns of correlations with needs measured by the Personality Research Form. More specifically, while the needs for Autonomy and Change correlate significantly with the Job Choice measure, they are uncorrelated with the Would Like measure. These results suggest that the two measures of Growth Need Strength map not be measuring the same underlying construct. This observation is bolstered by the fact that the observed and corrected correlations between these two measures of Growth Need Strength are only 21 and .28, respectively. A comparison of the present study’s results with those of Aldag and Brief (1977) shows that the Job Choice measure of Growth Need Strength (common to both studies) has correlations of approximately the same magnitude with other measures of higher order needs. In the Aldag and Brief study, for example, the Job Choice measure correlated .344 and .349, respectively, with needs for Occupational Achievement and SelfActualization (police officer sample). In the present study the Job Choice measure showed a (corrected) correlation of .34 with the need for Achievement. (Note that in the present study the Would Like measure correlated .38 with the same need.) Taken together, the results of the
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present study and that of Aldag and Brief show only a low degree of convergence between the Growth Need Strength measures and other measures of higher order needs. Values Measured
by the Survey of Work Values
The present study’s results revealed only slight convergence between the two measures of Growth Need Strength and the values assessed by the Survey of Work Values. Only one of the six values was found to correlate significantly with the Job Choice measure of Growth Need Strength. The observed correlation was, however, quite low (i.e., .18). And, while four of the six measures of work-related values were found to correlate significantly with the Would Like measure of Growth Need Strength, the largest of the observed correlations was only .26 (which when corrected increased to .3l). These results may serve to explain inconsistencies in the outcomes of previous research employing work values measures (e.g., Stone, 1975, 1976) as opposed to Higher Order Need Strength or Growth Need Strength measures (e.g., Hackman & Lawler, 1971; Hackman & Oldham, 1976) as moderators of relationships between job characteristics and individuals’ affective responses to jobs. Moreover, the results suggest that there may be only slight conceptual similarity between the individual differences moderators mentioned in such works as Hulin and Blood (1968), Hulin (1971), and Stone (1975, 1976), and those discussed in such works as Hackman and Lawler (1971) and Hackman and Oldham (1975, 1976). Similar to the findings associated with needs measured by the Personality Research Form, the Job Choice and Would Like measures of Growth Need Strength show generally dissimilar patterns of correlations with values indexed by the Survey of Work Values. The only work value that correlates significantly with both the Job Choice and Would Like measures is Upward Striving. Again, what is suggested is that the two measures of Growth Need Strength may not be representative of the same content domain. Research by Aldag and Brief (1977) revealed correlations between the Job Choice measure and Blood’s (1969) Protestant Ethic measure that ranged between .162 (hospital employee sample) and .290 (police officer sample). In the present study the Job Choice measure had a (corrected) correlation of .27 with the Upward Striving subscale of the Survey of Work Values. (The largest correlation for the Would Like measure, on the other hand, was .31 and involved the Pride in Work subscale.) Results of the present study and that of Aldag and Brief show a relatively low degree of convergence between Protestant Ethic values (either the measures of Blood or Wollack et al.) and scores produced by the Growth Need Strength scales.
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Zn$uence of Social Desirability Data from the present study revealed that both the Job Choice and the Would Like measures of Growth Need Strength are contaminated with social desirability response bias. In the case of the Job Choice measure the observed and corrected correlations are, respectively, .2l and .32. The corrected correlation suggests that Social Desirability accounts for only 10.2% of the variance in Job Choice scores. In the case of the Would Like measure of Growth Need Strength. however, the results are more damaging. The observed and corrected correlations between Social Desirability and the Would Like measure of Growth Need Strength are .36 and .50, respectively. The latter correlation suggesting that 25% of the variance in the Would Like measure can be accounted for by Social Desirability. The present study’s social desirability related results point to the need for further developmental work on the Growth Need Strength measures prior to their continued use in either basic or applied research. This need is obviously more critical in the case of the Would Like measure than it is in the case of the Job Choice measure. SUMMARY AND CONCLUSIONS Results of the present study, in sumnary form, are as follows: (a) There appears to be little convergence between the constructs indexed by the Would Like and Job Choice measures of Growth Need Strength; (b) needs measured by the Personality Research Form show modest and inconsistent relationships with the two Growth Need Strength measures: (c) values measured by the Survey of Work Values reveal generally low and inconsistent relationships with the Growth Need Strength measures; and (d) responses to both the Job Choice and Would Like measures of Growth Need Strength are contaminated by social desirability response bias. Three conclusions and/or recommendations appear warranted on the basis of these findings. First, results of research employing either of the two Growth Need Strength scales (or the earlier Higher-Order Need Strength measure of Hackman & Lawler. 1971) cannot be directly compared with the results of research employing measures of needs for Achievement, Autonomy, etc., and such work-related values as Job Involvement, Pride in Work, and Upward Striving. Growth Need Strength appears to share only modest proportions of variance with these other measures of individual differences. Second, given the relatively low degree of convergence between Growth Need Strength scale scores and other needs and values detected in the present study and that of Aldag and Brief (1977), consideration should be given to changing the label attached to scores produced by the Job Choice and Would Like measures. It would appear that these
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two measures index a person’s “preferences for degrees of job enrichment”-not a person’s general need for psychological growth. While it might be argued that “preferences for degrees ofjob enrichment” should be related to “needs for psychological growth,” it would appear unwarranted to assert that these constructs are equivalent. It would, therefore, seem reasonable to suggest that rather than referring to scores produced by the Job Choice and Would Like scales as indices of Growth Need Strength, instead they should be referred to as indices of Preferences for Job Scope or Desires for Enriched Work. Third, it would appear that additional development of the Growth Need Strength scales is needed. A major reason for this is the lack of convergence between the Job Choice and Would Like measures of Growth Need Strength. Corrected for unreliability the two measures correlate only .28 with one another (indicating that they share only 7.8% common variance). Another reason for recommending further developmental work on these scales is the social desirability-related findings. The 25% shared variability between Social Desirability and the Would Like measure is particularly disturbing. A final reason for recommending more research is that little is presently known about the construct (especially convergent and discriminant) validity of the Growth Need Strength measures. It is hoped that the results of the present study will serve as an impetus for such additional research. REFERENCES Aldag, R. J., & Brief, A. P. Examination of a meaure of higher order need strength. In 0. Behling & J. C. Henderson (Eds.), Proceedings ofthe 20th annual conference: Midwest Acudemy of Management. Columbus: Ohio State University, 1977. Blood. M. R. Work values and job satisfaction. Journul of Applied Psychology. 1969, 53, 456-459. Brief, A. P., & Aldag. R. J. Employee reactions to job characteristics: A constructive replication. Journal of Applied Psychology, 1975, 60, 182-186. Cronbach, L. J. Coefficient alpha and the internal structure of tests. Psychometrika. I95 I, 16, 297-334. Ghiselli, E. E. Explorations in mnnagerial talent. Pacific Palisades. Ca.: Goodyear Publishing Co.. 1971. Hackman. J. R., & Lawler, E. E. Employee reactions to job characteristics. Journal of Applied Psychology, 1971, 55, 259-286. Hackman, J. R., & Oldham. G. R. Development of the job diagnostic survey. Journal of Applied Psychology, 1975, 60, 159-170. Hackman, J. R., & Oldham, G. R. Motivation through the design of work: Test of a theory. Orgunizutionul Behuvior and Human Performance, 1976, 16, 250279. Hulin, C. L. Individual differences and job enrichment. In J. R. Maher (Ed.), New perspectives in job enrichment. New York: Van Nostrand-Reinhold, 1971. Hulin, C. L., & Blood, M. R. Job enlargement. individual differences. and worker responses. Psychological Bulletin, 1968, 69, 41-55. Jackson. D. N. Personality Reseurch Form mum&. Goshen, N.Y.: Research Psychologists Press. 1967.
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Nunnally, J. C. Psychomerric theory. New York: McGraw-Hill, 1967. Schuler, R. Worker background and job satisfaction. Industrial and Labor Relations Review, 1973, 26, 851-853. Stone, E. F. The moderating effect of work-related values on the job scope-job satisfaction relationship. (Doctoral Dissertation, University of California, Irvine, 1974) Dissertation Absrracrs International, 1974, 35, 3082B. (University Microfilms No. 74-27. 381) Stone. E. F. Job scope, job satisfaction, and the Protestant ethic: A study of enlisted men in the U.S. Navy. Journal of Vocational Behavior, 1975. 7, 215-224. Stone, E. F. The moderating effect of work-related values on the job scope-job satisfaction relationship. Organizational Behavior and Human Performance, 1976. 15, 147-167. Stone, E. F., Mowday. R. T., & Porter, L. W. Higher order need strengths as moderators of the job scope-job satisfaction relationship. Journal of Applied Psychology, 1977. 62, 466-471. Turner, A. N., & Lawrence, P. R. Industrial jobs and rhe worker. Boston: Harvard University Press, 1965. Umstot, D. D., Bell, C. H.. & Mitchell, T. R. Effects ofjob enrichment and task goals on satisfaction and productivity: Implications for job design. Journal of Applied Psycho/ogy, 1976, 61, 379-394. Wanous, J. P. Individual differences and reactions to job characteristics. Journal ofApplied Psychology, 1974, 59, 616-622. Wollack, S., Goodale, J. G., Wijting. J. P.. & Smith, P. C. Development of the Survey of Work Values. Journal of Applied Psychology, 1971, 55, 331-338. Received:
August 7. 1978.