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Comparison of Dietary Intakes of Husbands and Wives
Comparison o f Dietary Intakes o f Husbands and Wives KELLYREAMS L O U K , ' E L I S A B E T HS C H A F E R , 'ROBERT B. S C H A F E R ,A~N D P A T R I C I AK E I T H ~ 'Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 5001 1-1120; 2Department of Sociology, Iowa State University, Ames, Iowa 5001 1-1120
ABSTRACT This study was designed to examine the similarities in husbands' and wives' dietary intake and to investigate these similarities in relationship to the life stage of the family. A semiquantitative food frequency questionnaire was completed separately by 151 married couples. Intraclass correlation coefficients for the energy.-adjusted nutrient intake of all husbands and wives ranged from 0.04 for iron intake to 0.38 for saturated fat intake. Simple linear regression of the husband's intake (dependent) on the wife's intake (independent) was significantly different from zero for most energy-adjusted nutrients. However, this pattern was not consistent across the family life stages.This suggests that although spouses' nutrient intakes are more similar than different, one spouse's nutrient intake may not be a particularly good indicator of the intake of the other spouse.These results have important implications for the design and evaluation of interventions to change the dietary habits of family members.
Participation in an intervention by one spouse appeared ofl l to affect the dietary behaviors of the other s p ~ u s e . ~ ~ " A the interventions cited were designed to change the dietary behaviors of the family by targeting one family member and assuming that the change would be passed on to all members. Each of these interventions presumed that because family members lived in the same home their diets would be similar. However, these interventions did not assess the diet of the nonparticipating family member prior to the intervention. Kolonel and Leel3,l4are one of the few research groups publishing data concerning the dietary assessment of husbands and wives. In one study, they concluded that the intakes of husbands and wives as a group were similar. Upon further investigation, they concluded that moderate correlation could be found for nutrient intake between husbands and wives as a group but that the correspondence within the husband-wife pair was not consistent for any nutrient. In addition to the effects husbands and wives have on each other's dietary intake, Cross et al.I5 and Schafer and Keith16 concluded that dietary interests and concerns and the importance of dietary information changed as the family moved through the life stages. O n e purpose of this study was to test whether the diets of husbands and wives are more similar than the diets of unrelated men and women. Second, we investigated the similarities and differences of dietary intake in relationship to the life stage of the family. While it may seem reasonable to assume that lifestyles and dietary habits of couples are similar, there is little published research to support such an assumption. For example, it is unlikely that intake is similar in many families purchasing their noon meal at work or school cafeterias. Even those who dine out together usually make individual choices that are different from each other. By examining the dietary intake of couples in relationship to the life stage or structure of the family, it may be determined that dietary intake is similar in certain life stages and different in others, Such information would be useful in tailoring intervention and education materials to better reach the intended target population. Not -
UNE 31:145-152,1999)
INTRODUCTION Past research has examined the influence the family has on the behaviors of its People who are married or have children report less risky health behaviors than do other individual^.^,^ Zimmerman and Connor5 reported that subjects trying to make behavior changes perceived family members to be more supportive and encouraging than friends or coworkers.Additionally, the subjects believed family members changed their behaviors to match the subject more often than friends or coworkers. Many educators have used the family's influence when designing interventions to affect or change health behaviors involving the entire family.6-9 .......................... Address for correspondence: Elisabeth Schafer, Human Nutritional Sciences Bldg, Ilepartment of Food Science and Human Nutrition, I A State Universlty,Ames, IA 5001 1-1 120: Fax: (51 5), 294-6193: E-mail: eschaferGI.iastate.edu. , 01999 SOCIETY FOR NUTRITION EDUCATION
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Louk et al./HUSBANDS' AND WIVES' DIETARY INTAKE
only would these findings be beneficial to educators, but they also may provide more insight into the use of spouse-surrogate dietary information in epidemiologic studies.
METHODS This study is part of the larger Family Relationships and Nutrition Study, which has been described elsewhere.17The subjects were 151 white married couples who lived in the same household and were selected in a random area sample, based on population concentration.The sample was designed so that all housing units in one state had an equal chance of being selected.Al1 subjects are parents and are representative of married couples with children in this state. Subjects were selected to represent one of the four life stages of the family: 1.
2.
3.
Young families: married couples with at least one child under 6 years of age living in the home, with the wife less than 45 years of age. Established families: married couples with no children under 6 years of age but at least one child between 6 and 18 years of age living in the home.The wife may be any age. Empty-nest families: married couples with no children under 18 years living in the home and with the wife's age between 45 and 59 years. Older families: married couples with no children under 18 years living in the home and with the wife's age over 59 years.
This research was approved by the institutional Human Subjects Review Committee. Professional interviewers administered two-part questionnaires separately to each member of 151 couples. The interviewers were employed by the university statistical laboratory.They had received the standard training provided by the laboratory, which also entered and managed all data. Demographic, social, and psychological information was gathered via interview.The second portion of the questionnaire, dietary information, was self-administered after instruction. While one spouse was completing one part of the questionnaire, the other was being interviewed. All questionnaires were completed in the subjects' homes in 1992. Height and weight were self-reported by the subjects. Body mass index (BMI) was calculated by dividing the subjects' weight in kilograms by their height in meters squared. Dietary data for the past year were collected using the long version of a semiquantitative food frequency questionnaire (SQFFQ) designed by Block et a1.18 and used by the ' ~ SQFFQ has been validated National Cancer I n s t i t ~ t e .The using middle-aged women,20 black and white men and women," and older men." Nutrient analysis was performed using the National Cancer Institute DIETANAL computer
Nutrient density was calculated by creating a factor equaling the sum of energy for an individual divided by 1000.The absolute value for a particular nutrient for the same individual was divided by this factor to produce an energy-adjusted nutrient intake value. This technique eliminates the differences in nutrient intake due to energy intake. Means and ranges of energy-adjusted nutrient intake are reported. We performed a normal probability test of all nutrient variables. For those dietary intake variables whose distributions were skewed, we performed a log transformation and then used the log transformed variables for all subsequent analyses. A four (life stage) by two (husband/wife) analysis of variance was computed to examine the effects of life stage and gender on nutrient intake. The extent of nutrient intake agreement within the husband-wife pair was assessed using intraclass correlation. Linear regression analysis was used to ascertain if the wives' nutrient intakes could be used to predict the husbands' nutrient intakes.The husbands' intake (Y) was regressed on the wives'intake (X).All statistical analyses were performed using the Statistical Analysis Software (SAS) computer pa~kage.'~
RESULTS O n e hundred and fifty-one white married couples living in the same household participated in this study in 1992. The husbands ranged in age from 24.0 to 87.0 years, the mean age being 49.8 years.The wives ranged in age from 23.0 to 82.0 years, the mean age being 47.5 years. Education was reported as the number of years of formal education completed.The mean years of education for all husbands was 13.7, and 13.4 for all wives. Average household income for all families was between $25,000 and $34,999 per year. The percentage of husbands and wives employed outside the home ranged from 17.6% for older wives to 74.1% for young wives and from 23.5% of older husbands to 98.3% of young husbands. This percentage decreased as the family life stage progressed. Length of marriage for all families averaged 25.1 years. Mean BMI for husbands was 27.1 k 4.7 and wives' mean BMI was 25.9 & 5.5. Mean BMI was not significantly different among the husbands or the wives for each subgroup. Mean percentage of energy from protein was not significantly different for all husbands compared to all wives.Wives reported significantly higher percentage of energy from carbohydrate than did husbands. Wives' mean percentage of energy from alcohol, percentage of energy from fat, and mean total energy were significantly lower than the means for husbands. Significant differences were not found for husbands and wives of each lifespan group (Table 1). The same trends that were seen in energy-adjusted intake for husbands and wives overall were observed when calculated by life stage (Table 2).The wives'intake was significantly greater than the husbands' for all nutrients except for iron. However, the differences were not significant when observed
May * June 1999
Journal of Nutrition EducationVolume 31 Number 3 Table 1.
147
Dietary composition for husbands and wives by life stage (mean i SD [range]) Young Families
Nutrient
(n = 33 Couples)
Established Families Empty-Nest Families (n = 52 Couples)
(n = 32 Couples)
Older Families
All Families
(n = 34 Couples)
(n = 151 Couples)
Percent of energy from fat Husbands Wives
* 6.8
39.1 i 6.8
35.9 i 8.3
38.0
(22.6-54.8)
(24.0-52.3)
(16.7-50.6)
(22.0-57.9)
40.1 37.4
* 8.9
(18.2-52.1)
36.5
* 8.1
(18.0-52.5)
36.4
* 8.2
(22.3-57.8)
34.9
* 7.3 * 8.2
(18.9-54.0)
38.4
* 7.3
(16.7-57.9) 36.3
* 8.3"
(18.0-57.8)
Percent of energy from protein Husbands Wives Percent of energy from carbohydrate Husbands Wives Percent of energy from alcohol Husbands Wives Total energy Husbands Wives
"Mean intakes of wives differ significantly from mean intakes of husbands according to analysis of variance (p < .05)
within the family life stages. As the family life stage progressed, the energy-adjusted intakes of fiber, vitamins, and minerals, except for calcium, tended to be greater for both spouses. The mean daily intake of fruit, 2.1 servings, for all wives was significantly higher than the mean daily fruit intake of 1.7 servings for husbands. Mean daily vegetable intake for all husbands and wives was not significantly different although the wives reported more servings of vegetables (3.1 servings) than did the husbands (2.7 servings). Although there were no statistically significant differences in daily intakes of fruits and vegetables between wives and husbands across the life stage groups, in general, wives had a higher mean daily fruit and vegetable intake than did husbands. The wives in our study reported a mean of 5.2 servings of fruits and vegetables a day and 4.4 servings a day were reported by the husbands. Both husbands and wives of the empty-nest and older families life stages achieved the 5 A Day goal. Empty-nest husbands reported a mean of 5.2 servings of fruits and vegetables a day; their wives' meaned 5.8 servings a day. Older husbands also reported less servings of fruits and vegetables (5.1 servings) than older wives (6.2 servings).The two younger life stages did not meet this goal,
with young husbands, young wives, established husbands, and established wives reporting 4.1,4.5,3.7, and 4.7 servings of fruits and vegetables a day, respectively. Generally, weak positive correlations were found for nutrient intakes using intraclass correlation coefficients (r,). After calculating the results for lifespan groups, a few negative correlations for nutrient intakes, indicating less withincouple agreement than between-couple agreement, were found (Table 3). The linear regression model was significantly different from zero for all husband-wife pairs for all energy-adjusted nutrient intakes, except for iron and protein. This indicates that, overall, the wife's energy-adjusted nutrient intake was not a good indicator of the husband's energy-adjusted nutrient intake. In contrast, when viewed by family life stage, more similarities were seen in nutrient intake within the couples and intakes tend to converge in later family stages (Table 4). The coefficient of determination (r2) values quantieing the amount of variance of the husband's intake that can be attributed to the wife's were modest for all husband-wife pairs in all of the lifespan groups.Values ranged from 0.001 for the energy-adjusted nutrient intake of protein for older families to 0.330 for the energy-adjusted nutrient intake
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Louk et al./HUSBANDS' AND WIVES' DIETARY INTAKE
Table 2.
Mean energy-adjusted nutrient intakes for husbands and wives by life stage (mean
Nutrient
Young Families (n = 33 Couples)
i
SD [range]).
Established Families Empty-Nest Families (n = 52 Couples)
(n = 32 Couples)
Older Families
All Families
(n = 34 Couples)
(n = 151 Couples)
Dietary fiber (g) Husbands Wives Vitamin A (RE) Husbands Wives Vitamin C (mg) Husbands Wives Folate (pg) Husbands Wives Calcium (mg) Husbands Wives Iron (mg) Husbands Wives
aMean intakes of all wives differ significantly from mean intakes of all husbands according to analysis of variance (p < .05).
Table 3.
lntraclass correlation (r,) for daily energy-adjusted nutrient intake within the husband-wife pair for all life stages. -
Young Famlbes Characteristics Total energy Carbohydrate Protein Fat Saturated fat Cholesterol Dietary fiber Vitamin A Vitamin C Folate Iron Calcium
(n = 33 Couples)
Establrshed Famrlles Empty-Nest Famrlles (n = 52 Couples)
(n = 32 Couples)
-
-
-
Older Fam111es
All Famrhes
(n = 34 Couples)
(n = 151 Couples)
May
Journal of Nutrition Education Volume 31 Number 3 Table 4.
June
1999
149
Coefficient of determination (r2) for daily energy-adjusted nutrient intake within the husband-wife pair for all life stages.
Characteristics
Young Families (n = 33 Couples)
Established Families Empty-Nest Families
(n = 52 Couples)
(n = 32 Couples)
Older Families (n = 34 Couples)
All Families (n = 151 Couples)
Total energy
0.01 1
0.005
0.003
0.076
Carbohydrate
0.330"
0.002
0.112
0.092
0.009 0.077a
Protein
0.105
0.005
0.025
0.001
0.010
Fat
0.236"
0.041
0.010
0.01 5
0.075a
Saturated fat
0.21 2a
0.1 72"
0.114
0.243a
0.201"
Cholesterol
0.22ga
0.323"
0.085
0.065
0.158"
Dietary fiber
0.069
0.200a
0.1 60a
0.060
0.170a
Vitamin A
0.113
0.167a
0.097
0.1 17a
0.169"
Vitamin C
0.1 89"
0.166a
0.066
0.267a
0.1 93"
Folate
0.01 5
0.152a
0.035
0.009
0.083a
Iron
0.002
0.002
0.076
0.004
0.001
Calcium
0.1 28a
0.142a
0.037
0.007
0.035"
aThe simple linear model is significantly different from zero (p < .05).
value for carbohydrate for young families. Extent of agreement within the couple was poor to moderate (Table 4).
DISCUSSION The purposes of this research have been to determine similarities in husbands' and wives' diets and the relationship of these similarities to the life stage of the family.The design of this study was different from most dietary assessnlent research in that the spouses were interviewed separately. By interviewing the husband and wife individually, in different rooms of their home, we were able to prevent possible communication between the two that could have biased the results.We believe this method provides a more appropriate comparison of husbands' and wives' dietary intake than interviewing the couples together. O n e problem in all dietary intake studies involving recall is the accuracy of memory. Several studies have shown that However, in our current diet distorts memory ofpast diet.24.25 study, because the SQFFQ asks for current and recent habitual intake, the distancing effect is minimized. A potential bias in a study comparing dietary intakes of men and women is their differential memory for selected behaviors. Studies have shown that recall of body size in the past is poorer for men than for womenz6 but accuracy of recalled smoking behaviorz7 and physical activity2' does not differ by sex.The initial stage of memory requires attention or focus on the behavior to be remembered. It is tempting to assume that men's attention to eating is less focused than is women's or, to state it another way, due to traditional sex roles, is less salient for men than for women. By extension, then, one might hypothesize that memory of dietary behavior is less accurate for men than for women. Dwyer et al.24 reported, however, that sex of the respondent was only associated with accuracy of recall of grain consumption and was
not associated with accuracy of intake recall of any other food group such as eggs, alcohol, dairy products, fruits, or vegetables. The issue of memory bias in men and women is an intriguing question that bears on our results and should be investigated in future epidemiologic and dietary assessment studies. Nutrient intakes for husbands and wives could be expressed as absolute nutrient intake values or energyadjusted nutrient intake values. Because males tend to have higher nutrient intakes, one might expect to see more significant differences between the absolute nutrient intake values for husbands and wives.These results were seen in Lee and Kolonel'sI4 study of married couples as well as results for men and women from the 1987-88 National Food Consumption S ~ r v e y and ' ~ the 1987 National Health Interview Survey.'" However, absolute nutrient intake values do not allow for comparison on a similar basis and do not reflect variation in nutrient intake because of body size or activity. We chose to evaluate nutrient intake on an energy-adjusted basis rather than an absolute basis to allow for a similar conlparison of nutrient intake. After adjusting for total energy consumption, we found wives' intake of carbohydrate, protein, dietary fiber, vitamins, and minerals to be generally greater than the husbands' intake.This finding indicates that nutrient intake, not adjusted for energy intake, can be misleading. O u r data generally indicate a more nutrient-dense diet for wives that may be due to wives' higher consumption of fruits and vegetables. Emmons et al." found women generally consumed "healthier" diets and had higher consumption of micronutrients when adjusted for energy intake than did men. Morris et al.32also found female employees consuming more fruits, vegetables high in vitamin A, poultry, and fish than the male employees prior to a worksite intervention. Interestingly, energy-adjusted nutrient intakes of fiber, vitamins, and minerals, except for calcium, for both sexes had a
150
Louk et al./HUSBANDS' AND WIVES' DIETARY INTAKE
tendency to be greater as the family life stage progressed (see ommended, it was still more than adequate based on the subTable 3).These results could be supported by a greater conjects' BMI. However, body weight and height were selfreported by the subjects and not measured by the intersumption of fruits and vegetables by the older couples in our viewers.This fact and the wide ranges for BMI within each sample population.Absolute intakes reported in the 1987-88 National Food Consumption Survey29and the 1987 National family life stage could indicate some bias in reporting. Health Interview Survey30 revealed similar trends in vitamin Agreement in mean group nutrient intakes is not necesA, vitamin C, vitamin E, and folate intakes.Calcium intake sarily representative of the correspondence of nutrient intakes was lower in these surveys as the age of the subject increased. within the husband-wife pair.14 In our study, intraclass correlation indicated fair correlation for some, but not all, This may be because of greater incidence of lactose intolerenergy-adjusted nutrient intakes. ance with age, or perhaps milk is no longer kept in the home O u r intraclass correlation coefficients were not as strong when children are n o longer there. as those seen in Lee and Kolonel's14 research.A reason for this O u r results imply that the older couples tended to have a difference is that our study presented nutrient intake adjusted more nutrient-dense diet, with respect to vitamin and iron for energy intake rather than absolute nutrient intake values, intakes, than younger couples. This could be because of the as discussed earlier. Lee and Kolonel also reported nutrient different factors influencing food habits at each life stage. intake per kilogram of body weight. Because men tend to Older couples no longer have children living in the home have more muscle mass than women,37a kilogram of body and have only the food preferences of two people rather than ~~ weight for men would, theoretically, have a different metaa larger family to influence their decisions. K i n ~ e yreported bolic rate than a kilogram of body weight for women.Thus, that children have a tendency to consume more milk prodwe preferred to adjust for energy intake by computing nutriucts, snack foods, and sweet beverages and fewer fruits and ent density rather than nutrient intake per kilogram of body vegetables than other age groups. This pattern could influweight. ence the food consumption of the parents because food of '~ Additionally, the couples in Lee and K o l o n e l ' ~ research these types is more likely to be in the home. As individuals were all over age 45 while our couples ranged in age from age, they tend to become more aware of their own mortal23 to 87 years.We have shown that the correlation between ity. This may cause empty-nest and older families to make husband's and wife's energy-adjusted nutrient intake had a dietary changes for personal reasons as well as for reasons rectendency to be stronger in the empty-nest families life stage ommended by a doctor because of medical problems. Morthan in the established families life stage. Negative correlaris et al.32noted that older employees reported eating more tion, indicating less within-couple agreement than betweenfoods in the "believed-protective-against-cancer" category, couple agreement, was seen more often in the younger cousuch as fruits, vegetables, and high-fiber foods. This could ples. Perhaps younger couples have meals together less often account for the greater amount of fruits and vegetables conbecause of work and the activities of a young family and .~~ sumed by elderly people as reported by K i n ~ e yAdditionolder families eat together more often because of the comally, the nutrient intake values for empty-nest husbands and patibility of their schedules. Such a situation could explain wives are the least likely to be significantly different when the lesser agreement within a young husband and wife coucompared to the other life stages.This could be reflective of ple. Furthermore, examination into who has the primary an adjustment period in the life of the family where husbands responsibility for the procurement and preparation of food and wives, after spending years of eating apart because of may lend some ideas as to why this trend has been seen. work and children's schedules, are now starting to eat Last, and probably of most importance, the couples in our together again. research were interviewed separately and thus were not able Because significant differences were noted in energyto discuss their food intake with one another during the adjusted intakes in the overall group and were not seen interview process.The couples in Lee and Kolonel's study14 within the life stage, differences in nutrient intakes may be were interviewed together and discussion was allowed occurring across the life stages. Further research is needed to between the couples, which may have contaminated their determine if nutrient intakes change as the family life stage responses. changes. In spite of the fact that Lee and Kolonel14 found moderFat intake of husbands and wives was reported to be ate husband-wife agreement in nutrient intakes and our findgreater than 30% of energy intake, regardless of life stage group. T h e Third R e p o r t o n Nutrition M ~ n i t o r i n g ~ ~ ings that within-couple responses are more likely to agree than between-couple responses, within-couple agreement reported the median percentage of energy from fat in was still only fair at best. Wives' energy-adjusted intake was 1988-91 to be 34%, slightly lower than the average intake of not a good predictor of husbands' energy-adjusted intake. our couples. O u r coefficients of determination were much lower than Reported mean energy intakes for husbands and wives those seen elsewhere,14 suggesting that the variation in were below the recommended levels.35Mean BMI values intakes had more to do with factors other than the effect of were in the upper end of the "normal" range36 for all age one spouse's intake on the other.Within each life stage, fewer groups except for older wives. This might lead one to connutrients were significantly different from zero than in the clude that although reported energy intake was less than rec-
May
Journal of Nutrition EducationVolume 31 N u m b e r 3
overall group, and this improved as the family life stage aged. This implies that wife's intake was a better predictor of husband's intake as the family aged. In spite of the fact that the coefficient of determination values improved as the couple aged, they remained low. In conclusion, we found that agreement in nutrient intake within the husband-wife pair was weak. We conclude that using a spouse to predict the nutrient intake of the other is imprecise. O u r data do not support the presumption that adult family members eat a similar diet. Although the intraclass correlation coefficients for empty-nest families were generally improved over those for the established families, the agreement within the couple was never strong.
June 1999
151
7. Knutsen SF, Knutsen R.TheTromso Heart Study: the family intervention study-the
effect of intervention on some coronary risk factors
and dietary habits, a 6-year follow-up. Prev Med 1991;20:197-212. 8. Johnson CC, Harahsa DW, Powers CR,Webber LS, Berenson GS. Fort Polk Heart Smart Program Part IV: lifestyles of military personnel and their families. Mil Med 1993;158:317-22. 9. Nicklas TA, Johnson CC, Arbeit ML, Franklin FA, Berenson GS. A dynamic family approach for the prevention of cardiovascular disease. J Am Diet Assoc 1988;88:1438-40. 10. Zimmerman RS, GeraceTA, Smith JC, Benezra J.The effects of a worksite health promotion program on the wives of fire fighters. Soc Sci Med 1988;26:537-43. 11. White E, Hurlich M,Thompson RS, et al. Dietary changes among husbands of participants in low-fat dietary interventions. Am J Prev Med 1991;7:319-25.
IMPLICATIONS F O R RESEARCH A N D PRACTICE
12. ShattuckAL,White E, Kristol AR. How women's adopted low-fat diets
Further research is needed to explore the increasing congruence seen with age in the husband-wife dyad such as studying food procurement and preparation. These results may be generalized to white married couples with children; however, they may not be representative of other population groups.As previously mentioned, this study is part of a much larger longitudinal study that follows these couples as they progress through the family stages. This allows the research team to gain more information regarding the effect each stage has on the individual couples. Last, the research has some implications for using data from one spouse to reflect the intake of another, which could result in imprecise and inaccurate conclusions. This study has important implications for nutrition educators.As practitioners, these results could change the way we design and implement interventions aimed to change the dietary behaviors of the family. Interventions may need to be adapted to fit the life stage of the family. If couples do not have similar dietary intakes and behaviors, the social support needed for change may not be present, thus making it even more difficult to implement an intervention.
13. Kolonel LN, Lee J. Husband-wife correspondence in smoking, drink-
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in a worksite population. Eur J Clin Nutr 1995;49:336-45. 32. Morris DH, Sorensen G, Stoddard AM, Fitzgerald G. Comparison between food choices of working adults and dietary patterns recom-
1996:23-38. 37. Wilmore JH.The appllcatlon of science to sport: physiological profiles of male and female athletes. Can J Appl Sport Sci 1979;4:103-15.
The Administration on Children,Youth and Families, Department of Health and Human Services, in collaboration with Columbia University and the Society for Research in Child Development, announces Head Start's Fifth National Research Conference, "Development and Contextual Transitions of Children and Families: Implications for Research, Policy and Practice," to be held June 28-July 1,2000, in Washington, DC. The Call for Papers will be mailed and available at the Website on March 1, 1999. Proposals are due on July 15, 1999.All inquiries about the Call for Papers or the conference details should be directed to Dr. Faith Lamb-Parker, Project Director, Columbia School of Public Health/CPFH, 60 Haven Avenue B3, NewYork, NY 10032, [email protected], (212) 304-5251; Fax: (212) 544-1911, Website Address: http://www.scf.dhhs.gov/programs/hsb or h t t p : / / c p m c n e t . c o L u m b i a . e d u / d e p t / s p h / popfam.headstatr.htm1.
ABSTRACT This study was designed to examine the similarities in husbands' and wives' dietary intake and to investigate these similarities in relationship to the life stage of the family. A semiquantitative food frequency questionnaire was completed separately by 151 married couples. Intraclass correlation coefficients for the energy.-adjusted nutrient intake of all husbands and wives ranged from 0.04 for iron intake to 0.38 for saturated fat intake. Simple linear regression of the husband's intake (dependent) on the wife's intake (independent) was significantly different from zero for most energy-adjusted nutrients. However, this pattern was not consistent across the family life stages.This suggests that although spouses' nutrient intakes are more similar than different, one spouse's nutrient intake may not be a particularly good indicator of the intake of the other spouse.These results have important implications for the design and evaluation of interventions to change the dietary habits of family members.
Participation in an intervention by one spouse appeared ofl l to affect the dietary behaviors of the other s p ~ u s e . ~ ~ " A the interventions cited were designed to change the dietary behaviors of the family by targeting one family member and assuming that the change would be passed on to all members. Each of these interventions presumed that because family members lived in the same home their diets would be similar. However, these interventions did not assess the diet of the nonparticipating family member prior to the intervention. Kolonel and Leel3,l4are one of the few research groups publishing data concerning the dietary assessment of husbands and wives. In one study, they concluded that the intakes of husbands and wives as a group were similar. Upon further investigation, they concluded that moderate correlation could be found for nutrient intake between husbands and wives as a group but that the correspondence within the husband-wife pair was not consistent for any nutrient. In addition to the effects husbands and wives have on each other's dietary intake, Cross et al.I5 and Schafer and Keith16 concluded that dietary interests and concerns and the importance of dietary information changed as the family moved through the life stages. O n e purpose of this study was to test whether the diets of husbands and wives are more similar than the diets of unrelated men and women. Second, we investigated the similarities and differences of dietary intake in relationship to the life stage of the family. While it may seem reasonable to assume that lifestyles and dietary habits of couples are similar, there is little published research to support such an assumption. For example, it is unlikely that intake is similar in many families purchasing their noon meal at work or school cafeterias. Even those who dine out together usually make individual choices that are different from each other. By examining the dietary intake of couples in relationship to the life stage or structure of the family, it may be determined that dietary intake is similar in certain life stages and different in others, Such information would be useful in tailoring intervention and education materials to better reach the intended target population. Not -
UNE 31:145-152,1999)
INTRODUCTION Past research has examined the influence the family has on the behaviors of its People who are married or have children report less risky health behaviors than do other individual^.^,^ Zimmerman and Connor5 reported that subjects trying to make behavior changes perceived family members to be more supportive and encouraging than friends or coworkers.Additionally, the subjects believed family members changed their behaviors to match the subject more often than friends or coworkers. Many educators have used the family's influence when designing interventions to affect or change health behaviors involving the entire family.6-9 .......................... Address for correspondence: Elisabeth Schafer, Human Nutritional Sciences Bldg, Ilepartment of Food Science and Human Nutrition, I A State Universlty,Ames, IA 5001 1-1 120: Fax: (51 5), 294-6193: E-mail: eschaferGI.iastate.edu. , 01999 SOCIETY FOR NUTRITION EDUCATION
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Louk et al./HUSBANDS' AND WIVES' DIETARY INTAKE
only would these findings be beneficial to educators, but they also may provide more insight into the use of spouse-surrogate dietary information in epidemiologic studies.
METHODS This study is part of the larger Family Relationships and Nutrition Study, which has been described elsewhere.17The subjects were 151 white married couples who lived in the same household and were selected in a random area sample, based on population concentration.The sample was designed so that all housing units in one state had an equal chance of being selected.Al1 subjects are parents and are representative of married couples with children in this state. Subjects were selected to represent one of the four life stages of the family: 1.
2.
3.
Young families: married couples with at least one child under 6 years of age living in the home, with the wife less than 45 years of age. Established families: married couples with no children under 6 years of age but at least one child between 6 and 18 years of age living in the home.The wife may be any age. Empty-nest families: married couples with no children under 18 years living in the home and with the wife's age between 45 and 59 years. Older families: married couples with no children under 18 years living in the home and with the wife's age over 59 years.
This research was approved by the institutional Human Subjects Review Committee. Professional interviewers administered two-part questionnaires separately to each member of 151 couples. The interviewers were employed by the university statistical laboratory.They had received the standard training provided by the laboratory, which also entered and managed all data. Demographic, social, and psychological information was gathered via interview.The second portion of the questionnaire, dietary information, was self-administered after instruction. While one spouse was completing one part of the questionnaire, the other was being interviewed. All questionnaires were completed in the subjects' homes in 1992. Height and weight were self-reported by the subjects. Body mass index (BMI) was calculated by dividing the subjects' weight in kilograms by their height in meters squared. Dietary data for the past year were collected using the long version of a semiquantitative food frequency questionnaire (SQFFQ) designed by Block et a1.18 and used by the ' ~ SQFFQ has been validated National Cancer I n s t i t ~ t e .The using middle-aged women,20 black and white men and women," and older men." Nutrient analysis was performed using the National Cancer Institute DIETANAL computer
Nutrient density was calculated by creating a factor equaling the sum of energy for an individual divided by 1000.The absolute value for a particular nutrient for the same individual was divided by this factor to produce an energy-adjusted nutrient intake value. This technique eliminates the differences in nutrient intake due to energy intake. Means and ranges of energy-adjusted nutrient intake are reported. We performed a normal probability test of all nutrient variables. For those dietary intake variables whose distributions were skewed, we performed a log transformation and then used the log transformed variables for all subsequent analyses. A four (life stage) by two (husband/wife) analysis of variance was computed to examine the effects of life stage and gender on nutrient intake. The extent of nutrient intake agreement within the husband-wife pair was assessed using intraclass correlation. Linear regression analysis was used to ascertain if the wives' nutrient intakes could be used to predict the husbands' nutrient intakes.The husbands' intake (Y) was regressed on the wives'intake (X).All statistical analyses were performed using the Statistical Analysis Software (SAS) computer pa~kage.'~
RESULTS O n e hundred and fifty-one white married couples living in the same household participated in this study in 1992. The husbands ranged in age from 24.0 to 87.0 years, the mean age being 49.8 years.The wives ranged in age from 23.0 to 82.0 years, the mean age being 47.5 years. Education was reported as the number of years of formal education completed.The mean years of education for all husbands was 13.7, and 13.4 for all wives. Average household income for all families was between $25,000 and $34,999 per year. The percentage of husbands and wives employed outside the home ranged from 17.6% for older wives to 74.1% for young wives and from 23.5% of older husbands to 98.3% of young husbands. This percentage decreased as the family life stage progressed. Length of marriage for all families averaged 25.1 years. Mean BMI for husbands was 27.1 k 4.7 and wives' mean BMI was 25.9 & 5.5. Mean BMI was not significantly different among the husbands or the wives for each subgroup. Mean percentage of energy from protein was not significantly different for all husbands compared to all wives.Wives reported significantly higher percentage of energy from carbohydrate than did husbands. Wives' mean percentage of energy from alcohol, percentage of energy from fat, and mean total energy were significantly lower than the means for husbands. Significant differences were not found for husbands and wives of each lifespan group (Table 1). The same trends that were seen in energy-adjusted intake for husbands and wives overall were observed when calculated by life stage (Table 2).The wives'intake was significantly greater than the husbands' for all nutrients except for iron. However, the differences were not significant when observed
May * June 1999
Journal of Nutrition EducationVolume 31 Number 3 Table 1.
147
Dietary composition for husbands and wives by life stage (mean i SD [range]) Young Families
Nutrient
(n = 33 Couples)
Established Families Empty-Nest Families (n = 52 Couples)
(n = 32 Couples)
Older Families
All Families
(n = 34 Couples)
(n = 151 Couples)
Percent of energy from fat Husbands Wives
* 6.8
39.1 i 6.8
35.9 i 8.3
38.0
(22.6-54.8)
(24.0-52.3)
(16.7-50.6)
(22.0-57.9)
40.1 37.4
* 8.9
(18.2-52.1)
36.5
* 8.1
(18.0-52.5)
36.4
* 8.2
(22.3-57.8)
34.9
* 7.3 * 8.2
(18.9-54.0)
38.4
* 7.3
(16.7-57.9) 36.3
* 8.3"
(18.0-57.8)
Percent of energy from protein Husbands Wives Percent of energy from carbohydrate Husbands Wives Percent of energy from alcohol Husbands Wives Total energy Husbands Wives
"Mean intakes of wives differ significantly from mean intakes of husbands according to analysis of variance (p < .05)
within the family life stages. As the family life stage progressed, the energy-adjusted intakes of fiber, vitamins, and minerals, except for calcium, tended to be greater for both spouses. The mean daily intake of fruit, 2.1 servings, for all wives was significantly higher than the mean daily fruit intake of 1.7 servings for husbands. Mean daily vegetable intake for all husbands and wives was not significantly different although the wives reported more servings of vegetables (3.1 servings) than did the husbands (2.7 servings). Although there were no statistically significant differences in daily intakes of fruits and vegetables between wives and husbands across the life stage groups, in general, wives had a higher mean daily fruit and vegetable intake than did husbands. The wives in our study reported a mean of 5.2 servings of fruits and vegetables a day and 4.4 servings a day were reported by the husbands. Both husbands and wives of the empty-nest and older families life stages achieved the 5 A Day goal. Empty-nest husbands reported a mean of 5.2 servings of fruits and vegetables a day; their wives' meaned 5.8 servings a day. Older husbands also reported less servings of fruits and vegetables (5.1 servings) than older wives (6.2 servings).The two younger life stages did not meet this goal,
with young husbands, young wives, established husbands, and established wives reporting 4.1,4.5,3.7, and 4.7 servings of fruits and vegetables a day, respectively. Generally, weak positive correlations were found for nutrient intakes using intraclass correlation coefficients (r,). After calculating the results for lifespan groups, a few negative correlations for nutrient intakes, indicating less withincouple agreement than between-couple agreement, were found (Table 3). The linear regression model was significantly different from zero for all husband-wife pairs for all energy-adjusted nutrient intakes, except for iron and protein. This indicates that, overall, the wife's energy-adjusted nutrient intake was not a good indicator of the husband's energy-adjusted nutrient intake. In contrast, when viewed by family life stage, more similarities were seen in nutrient intake within the couples and intakes tend to converge in later family stages (Table 4). The coefficient of determination (r2) values quantieing the amount of variance of the husband's intake that can be attributed to the wife's were modest for all husband-wife pairs in all of the lifespan groups.Values ranged from 0.001 for the energy-adjusted nutrient intake of protein for older families to 0.330 for the energy-adjusted nutrient intake
148
Louk et al./HUSBANDS' AND WIVES' DIETARY INTAKE
Table 2.
Mean energy-adjusted nutrient intakes for husbands and wives by life stage (mean
Nutrient
Young Families (n = 33 Couples)
i
SD [range]).
Established Families Empty-Nest Families (n = 52 Couples)
(n = 32 Couples)
Older Families
All Families
(n = 34 Couples)
(n = 151 Couples)
Dietary fiber (g) Husbands Wives Vitamin A (RE) Husbands Wives Vitamin C (mg) Husbands Wives Folate (pg) Husbands Wives Calcium (mg) Husbands Wives Iron (mg) Husbands Wives
aMean intakes of all wives differ significantly from mean intakes of all husbands according to analysis of variance (p < .05).
Table 3.
lntraclass correlation (r,) for daily energy-adjusted nutrient intake within the husband-wife pair for all life stages. -
Young Famlbes Characteristics Total energy Carbohydrate Protein Fat Saturated fat Cholesterol Dietary fiber Vitamin A Vitamin C Folate Iron Calcium
(n = 33 Couples)
Establrshed Famrlles Empty-Nest Famrlles (n = 52 Couples)
(n = 32 Couples)
-
-
-
Older Fam111es
All Famrhes
(n = 34 Couples)
(n = 151 Couples)
May
Journal of Nutrition Education Volume 31 Number 3 Table 4.
June
1999
149
Coefficient of determination (r2) for daily energy-adjusted nutrient intake within the husband-wife pair for all life stages.
Characteristics
Young Families (n = 33 Couples)
Established Families Empty-Nest Families
(n = 52 Couples)
(n = 32 Couples)
Older Families (n = 34 Couples)
All Families (n = 151 Couples)
Total energy
0.01 1
0.005
0.003
0.076
Carbohydrate
0.330"
0.002
0.112
0.092
0.009 0.077a
Protein
0.105
0.005
0.025
0.001
0.010
Fat
0.236"
0.041
0.010
0.01 5
0.075a
Saturated fat
0.21 2a
0.1 72"
0.114
0.243a
0.201"
Cholesterol
0.22ga
0.323"
0.085
0.065
0.158"
Dietary fiber
0.069
0.200a
0.1 60a
0.060
0.170a
Vitamin A
0.113
0.167a
0.097
0.1 17a
0.169"
Vitamin C
0.1 89"
0.166a
0.066
0.267a
0.1 93"
Folate
0.01 5
0.152a
0.035
0.009
0.083a
Iron
0.002
0.002
0.076
0.004
0.001
Calcium
0.1 28a
0.142a
0.037
0.007
0.035"
aThe simple linear model is significantly different from zero (p < .05).
value for carbohydrate for young families. Extent of agreement within the couple was poor to moderate (Table 4).
DISCUSSION The purposes of this research have been to determine similarities in husbands' and wives' diets and the relationship of these similarities to the life stage of the family.The design of this study was different from most dietary assessnlent research in that the spouses were interviewed separately. By interviewing the husband and wife individually, in different rooms of their home, we were able to prevent possible communication between the two that could have biased the results.We believe this method provides a more appropriate comparison of husbands' and wives' dietary intake than interviewing the couples together. O n e problem in all dietary intake studies involving recall is the accuracy of memory. Several studies have shown that However, in our current diet distorts memory ofpast diet.24.25 study, because the SQFFQ asks for current and recent habitual intake, the distancing effect is minimized. A potential bias in a study comparing dietary intakes of men and women is their differential memory for selected behaviors. Studies have shown that recall of body size in the past is poorer for men than for womenz6 but accuracy of recalled smoking behaviorz7 and physical activity2' does not differ by sex.The initial stage of memory requires attention or focus on the behavior to be remembered. It is tempting to assume that men's attention to eating is less focused than is women's or, to state it another way, due to traditional sex roles, is less salient for men than for women. By extension, then, one might hypothesize that memory of dietary behavior is less accurate for men than for women. Dwyer et al.24 reported, however, that sex of the respondent was only associated with accuracy of recall of grain consumption and was
not associated with accuracy of intake recall of any other food group such as eggs, alcohol, dairy products, fruits, or vegetables. The issue of memory bias in men and women is an intriguing question that bears on our results and should be investigated in future epidemiologic and dietary assessment studies. Nutrient intakes for husbands and wives could be expressed as absolute nutrient intake values or energyadjusted nutrient intake values. Because males tend to have higher nutrient intakes, one might expect to see more significant differences between the absolute nutrient intake values for husbands and wives.These results were seen in Lee and Kolonel'sI4 study of married couples as well as results for men and women from the 1987-88 National Food Consumption S ~ r v e y and ' ~ the 1987 National Health Interview Survey.'" However, absolute nutrient intake values do not allow for comparison on a similar basis and do not reflect variation in nutrient intake because of body size or activity. We chose to evaluate nutrient intake on an energy-adjusted basis rather than an absolute basis to allow for a similar conlparison of nutrient intake. After adjusting for total energy consumption, we found wives' intake of carbohydrate, protein, dietary fiber, vitamins, and minerals to be generally greater than the husbands' intake.This finding indicates that nutrient intake, not adjusted for energy intake, can be misleading. O u r data generally indicate a more nutrient-dense diet for wives that may be due to wives' higher consumption of fruits and vegetables. Emmons et al." found women generally consumed "healthier" diets and had higher consumption of micronutrients when adjusted for energy intake than did men. Morris et al.32also found female employees consuming more fruits, vegetables high in vitamin A, poultry, and fish than the male employees prior to a worksite intervention. Interestingly, energy-adjusted nutrient intakes of fiber, vitamins, and minerals, except for calcium, for both sexes had a
150
Louk et al./HUSBANDS' AND WIVES' DIETARY INTAKE
tendency to be greater as the family life stage progressed (see ommended, it was still more than adequate based on the subTable 3).These results could be supported by a greater conjects' BMI. However, body weight and height were selfreported by the subjects and not measured by the intersumption of fruits and vegetables by the older couples in our viewers.This fact and the wide ranges for BMI within each sample population.Absolute intakes reported in the 1987-88 National Food Consumption Survey29and the 1987 National family life stage could indicate some bias in reporting. Health Interview Survey30 revealed similar trends in vitamin Agreement in mean group nutrient intakes is not necesA, vitamin C, vitamin E, and folate intakes.Calcium intake sarily representative of the correspondence of nutrient intakes was lower in these surveys as the age of the subject increased. within the husband-wife pair.14 In our study, intraclass correlation indicated fair correlation for some, but not all, This may be because of greater incidence of lactose intolerenergy-adjusted nutrient intakes. ance with age, or perhaps milk is no longer kept in the home O u r intraclass correlation coefficients were not as strong when children are n o longer there. as those seen in Lee and Kolonel's14 research.A reason for this O u r results imply that the older couples tended to have a difference is that our study presented nutrient intake adjusted more nutrient-dense diet, with respect to vitamin and iron for energy intake rather than absolute nutrient intake values, intakes, than younger couples. This could be because of the as discussed earlier. Lee and Kolonel also reported nutrient different factors influencing food habits at each life stage. intake per kilogram of body weight. Because men tend to Older couples no longer have children living in the home have more muscle mass than women,37a kilogram of body and have only the food preferences of two people rather than ~~ weight for men would, theoretically, have a different metaa larger family to influence their decisions. K i n ~ e yreported bolic rate than a kilogram of body weight for women.Thus, that children have a tendency to consume more milk prodwe preferred to adjust for energy intake by computing nutriucts, snack foods, and sweet beverages and fewer fruits and ent density rather than nutrient intake per kilogram of body vegetables than other age groups. This pattern could influweight. ence the food consumption of the parents because food of '~ Additionally, the couples in Lee and K o l o n e l ' ~ research these types is more likely to be in the home. As individuals were all over age 45 while our couples ranged in age from age, they tend to become more aware of their own mortal23 to 87 years.We have shown that the correlation between ity. This may cause empty-nest and older families to make husband's and wife's energy-adjusted nutrient intake had a dietary changes for personal reasons as well as for reasons rectendency to be stronger in the empty-nest families life stage ommended by a doctor because of medical problems. Morthan in the established families life stage. Negative correlaris et al.32noted that older employees reported eating more tion, indicating less within-couple agreement than betweenfoods in the "believed-protective-against-cancer" category, couple agreement, was seen more often in the younger cousuch as fruits, vegetables, and high-fiber foods. This could ples. Perhaps younger couples have meals together less often account for the greater amount of fruits and vegetables conbecause of work and the activities of a young family and .~~ sumed by elderly people as reported by K i n ~ e yAdditionolder families eat together more often because of the comally, the nutrient intake values for empty-nest husbands and patibility of their schedules. Such a situation could explain wives are the least likely to be significantly different when the lesser agreement within a young husband and wife coucompared to the other life stages.This could be reflective of ple. Furthermore, examination into who has the primary an adjustment period in the life of the family where husbands responsibility for the procurement and preparation of food and wives, after spending years of eating apart because of may lend some ideas as to why this trend has been seen. work and children's schedules, are now starting to eat Last, and probably of most importance, the couples in our together again. research were interviewed separately and thus were not able Because significant differences were noted in energyto discuss their food intake with one another during the adjusted intakes in the overall group and were not seen interview process.The couples in Lee and Kolonel's study14 within the life stage, differences in nutrient intakes may be were interviewed together and discussion was allowed occurring across the life stages. Further research is needed to between the couples, which may have contaminated their determine if nutrient intakes change as the family life stage responses. changes. In spite of the fact that Lee and Kolonel14 found moderFat intake of husbands and wives was reported to be ate husband-wife agreement in nutrient intakes and our findgreater than 30% of energy intake, regardless of life stage group. T h e Third R e p o r t o n Nutrition M ~ n i t o r i n g ~ ~ ings that within-couple responses are more likely to agree than between-couple responses, within-couple agreement reported the median percentage of energy from fat in was still only fair at best. Wives' energy-adjusted intake was 1988-91 to be 34%, slightly lower than the average intake of not a good predictor of husbands' energy-adjusted intake. our couples. O u r coefficients of determination were much lower than Reported mean energy intakes for husbands and wives those seen elsewhere,14 suggesting that the variation in were below the recommended levels.35Mean BMI values intakes had more to do with factors other than the effect of were in the upper end of the "normal" range36 for all age one spouse's intake on the other.Within each life stage, fewer groups except for older wives. This might lead one to connutrients were significantly different from zero than in the clude that although reported energy intake was less than rec-
May
Journal of Nutrition EducationVolume 31 N u m b e r 3
overall group, and this improved as the family life stage aged. This implies that wife's intake was a better predictor of husband's intake as the family aged. In spite of the fact that the coefficient of determination values improved as the couple aged, they remained low. In conclusion, we found that agreement in nutrient intake within the husband-wife pair was weak. We conclude that using a spouse to predict the nutrient intake of the other is imprecise. O u r data do not support the presumption that adult family members eat a similar diet. Although the intraclass correlation coefficients for empty-nest families were generally improved over those for the established families, the agreement within the couple was never strong.
June 1999
151
7. Knutsen SF, Knutsen R.TheTromso Heart Study: the family intervention study-the
effect of intervention on some coronary risk factors
and dietary habits, a 6-year follow-up. Prev Med 1991;20:197-212. 8. Johnson CC, Harahsa DW, Powers CR,Webber LS, Berenson GS. Fort Polk Heart Smart Program Part IV: lifestyles of military personnel and their families. Mil Med 1993;158:317-22. 9. Nicklas TA, Johnson CC, Arbeit ML, Franklin FA, Berenson GS. A dynamic family approach for the prevention of cardiovascular disease. J Am Diet Assoc 1988;88:1438-40. 10. Zimmerman RS, GeraceTA, Smith JC, Benezra J.The effects of a worksite health promotion program on the wives of fire fighters. Soc Sci Med 1988;26:537-43. 11. White E, Hurlich M,Thompson RS, et al. Dietary changes among husbands of participants in low-fat dietary interventions. Am J Prev Med 1991;7:319-25.
IMPLICATIONS F O R RESEARCH A N D PRACTICE
12. ShattuckAL,White E, Kristol AR. How women's adopted low-fat diets
Further research is needed to explore the increasing congruence seen with age in the husband-wife dyad such as studying food procurement and preparation. These results may be generalized to white married couples with children; however, they may not be representative of other population groups.As previously mentioned, this study is part of a much larger longitudinal study that follows these couples as they progress through the family stages. This allows the research team to gain more information regarding the effect each stage has on the individual couples. Last, the research has some implications for using data from one spouse to reflect the intake of another, which could result in imprecise and inaccurate conclusions. This study has important implications for nutrition educators.As practitioners, these results could change the way we design and implement interventions aimed to change the dietary behaviors of the family. Interventions may need to be adapted to fit the life stage of the family. If couples do not have similar dietary intakes and behaviors, the social support needed for change may not be present, thus making it even more difficult to implement an intervention.
13. Kolonel LN, Lee J. Husband-wife correspondence in smoking, drink-
affect their husbands.Am J Public Health 1992;82:1244-50. ing and dietary habits.Am J Clin Nutr 1981;34:99-104. 14. Lee J, Kolonel LN. Nutrient intakes of husbands and wives: implications for epidemiologic research. Am J Epidemiol 1982;115:515-25. 15. Cross B, Herrmann R0,Warland R H . Effect of family life-cycle stage on concerns about food selection. J Am Diet Assoc 1975;67:131-4. 16. Schafer RB, Keith PM. Influences on food decisions across the family life cycle. J Am Diet Assoc 1981;78:144-8. 17. Schafer RB, Keith PM, Schafer E. Predicting fat in diets of marital partners using the Health Belief Model. J Behav Med 1995;18:419-33. 18. Block G, Hartman AM, Dresser CM, Carroll MD, Gannon J, Gardner L.A data-based approach to diet questionnaire design and testing.Am J Epidemiol 1986;124:453-69. 19. Block G. Health habits and history questionnaire: diet history and other risk factors [personal computer system packet]. Bethesda, MD: National Cancer Institute, 1989. 20. Block G,Woods M, Potosky A, Clifford C.Valldation of a self-administered diet history questionnaire using multiple diet records. J Epidemiol 1990;43:1327-35. 21. Block G, Thompson FE, Hartman AM, Larkin FA, Guire KE. Comparison of two dietary questionnaires validated against multiple dietary records collected d u r i n g a 1-year period. J A m D i e t Assoc 1992;92:686-93. 22. Sobell J, Block G, Koslowe P,Tobin J,Andres R.Validation of a retro-
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The Administration on Children,Youth and Families, Department of Health and Human Services, in collaboration with Columbia University and the Society for Research in Child Development, announces Head Start's Fifth National Research Conference, "Development and Contextual Transitions of Children and Families: Implications for Research, Policy and Practice," to be held June 28-July 1,2000, in Washington, DC. The Call for Papers will be mailed and available at the Website on March 1, 1999. Proposals are due on July 15, 1999.All inquiries about the Call for Papers or the conference details should be directed to Dr. Faith Lamb-Parker, Project Director, Columbia School of Public Health/CPFH, 60 Haven Avenue B3, NewYork, NY 10032, [email protected], (212) 304-5251; Fax: (212) 544-1911, Website Address: http://www.scf.dhhs.gov/programs/hsb or h t t p : / / c p m c n e t . c o L u m b i a . e d u / d e p t / s p h / popfam.headstatr.htm1.