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Two short frequency questionnaires, the NCI 19-item Fruit and Vegetable Screener (FVS) and a single question on overall fruit and vegetable consumption (1-item), were evaluated for their ability to assess change in fruit and vegetable (FV) consumption over time and in response to intervention among participants in 5 health promotion trials in the Behavior Change Consortium. Cross-sectional differences and correlations of FV estimates at baseline and at follow-up were compared for the FVS (n = 3151 and the 1-item In = 2271, relative to multiple 24-h recall interviews (24HR). The FVS significantly overestimated daily intake by 1.27 servings at baseline among men and by 1.42 and 1.59 servings at baseline and follow-up, respectively, in women, whereas the 1-item measure significantly underestimated intake at both time points in men (0.98 serving at baseline, 0.75 serving at follow-up) and women (0.61 and 0.41 serving). Cross-sectional deattenuated correlations with 24H8 at follow-up were 0.48 (FVS) and 0.50 (1-item). To evaluate the capacity of the 2 screeners to assess FV change, we compared mean posttest effects with 24HR by treatment group overall and by gender. Treatment group differences were not significant for either 24HR or 1-item. Among 315 subjects, the FVS treatment group differences were significant both overall and within gender but not when repeated in the sample of 227. Findings suggest multiple 24HR at multiple time points in adequate sample sizes remain the gold standard for FV reports. Biases in FVS estimates may reflect participants' lifestyles and sociodemographic characteristics and require further examination in longitudinal samples representative of diverse populations. [ABSTRACT FROM AUTHOR]

The need for an inexpensive measure of dietary intake in intervention studies led to evaluation of the National Cancer Institute (NCI) Percentage Energy from Fat short instrument (PFat) in a subgroup of the Behavioral Change Consortium (BCC) intervention sites. The PEat's performance was evaluated using multiple nonconsecutive 24-h dietary recalls (24HR) as a reference instrument among participants at baseline in 4 demographically diverse intervention sites of the BCC. Mean estimates of percentage energy from fat for 24HR and PFat were within 2.1 percentage points of each other in all but 2 site/gender comparisons. 24HR and PEat estimates were not significantly different (P < 0.05) among men for 2 of 3 sites, and among women for 2 of 4 sites. Deattenuated Pearson correlation coefficients for the PFat and true intake (as estimated from the 24HR using a measurement error model) were significantly different from 0 (P < 0.05) for men and women in all sites, ranging from 0.52 to 0.77 among men and 0.36 to 0.59 among women. Besides gender and site, no other factors examined (age, education, smoking status, and BMI) consistently moderated validity estimates. If accurate assessment of diet at baseline land presumably at follow-up) is essential, a more detailed instrument such as multiple 24HR may be warranted. The question of whether the PFat adequately measures change in diet is addressed in another article in this supplement. [ABSTRACT FROM AUTHOR]

Measurement of percentage energy from fat is important in surveillance of populations and in epidemiologic studies examining relationships between diet and disease as well as for behavioral intervention studies seeking to change dietary behavior. The NCI percentage energy from fat screener (PFat) has adequately predicted percentage of energy from fat compared with 24-h recalls (24HR) in cross-sectional analyses. However, the instrument has not been evaluated for its ability to assess change of percentage energy from fat over time or in response to interventions to change dietary intake of fat. The objective of this analysis is to evaluate the performance of the PFat in assessing change in percentage energy intake from fat in a behavioral intervention setting. Four individual sites participating in the Behavior Change Consortium Nutrition Working Group administered both the PF at and multiple 24HR at baseline and follow-up to 278 participants. A measurement error model was used to assess agreement between the PFat and 24HR at baseline and follow-up. The PFat was consistent with 24HR in finding there was no significant change in percentage energy from fat as a result of the intervention. Both male and female participants in the intervention group demonstrated a significant increase in the correlation between PFat and 24HR from baseline to follow-up. Percentage energy from fat measured by PFat may be useful to provide estimates of change in mean intake of populations over time in longitudinal studies. Further methodologic research is called for in interventions producing significant changes and in diverse populations with adequate sample size. [ABSTRACT FROM AUTHOR]

The purpose of this article is to describe the baseline design elements and sample characteristics of the Behavior Change Consortium (BCC) Dietary Measurement studies for each of the 7 sites that comprised the BCC Nutrition Working Group (NWG). This article summarizes the project designs, including descriptions of diverse study populations, primary assessment methods, and study outcomes. Common measures used across sites included the National Cancer Institute (NCI) Fruit and Vegetable Screener, NCI Percentage Energy from Fat Screener, 24-h dietary recalls, and a single- or 2-item fruit and vegetable measure. Data on sociodemographic characteristics, body weight and height, smoking status, and serum carotenoids were also collected. Study design information such as assessment time points, as well as baseline sample characteristics, is also described. This paper provides the overall framework and descriptive information and serves as the reference for the BCC NWG special supplement. [ABSTRACT FROM AUTHOR]

Despite widespread use of dietary supplements, little is known about correlates and determinants of their use. Using a diverse sample from 7 interventions participating in the Behavior Change Consortium In = 2539), signal detection methodology (SDM) demonstrated a method for identifying subgroups with varying supplement use. An SDM model was explored with an exploratory half of the entire sample (n = 1268) and used 5 variables to predict dietary supplement use: cigarette smoking, fruit and vegetable intake, dietary fat consumption, BMI, and stage of change for physical activity. A comparison of rates of supplement use between the exploratory model groups and comparably identified groups in the reserved, confirmatory sample (n = 1271) indicates that these analyses may be generalizable. Significant indicators of any supplement use included smoking status, percentage of energy from fat, and fruit and vegetable consumption. Although higher supplement use was associated with healthy behaviors overall, many of the identified groups exhibited mixed combinations of healthy and unhealthy behaviors. The results of this study suggest that patterns of dietary supplement use are complex and support the use of SDM to identify possible population characteristics for targeted and tailored health communication interventions. [ABSTRACT FROM AUTHOR]

Five sites participating in the NCI Behavior Change Consortium administered the NCI Fruit and Vegetable Screener (FVS) and multiple, nonconsecutive 24-h dietary recall interviews (24HR) to 590 participants. Three sites also obtained serum carotenoids In = 295). Participants were primarily female, ethnically diverse, and varied by age and education. Correlations between 24HR and FVS by site ranged from 0.31 (P= 0.07) to 0.47 (P < 0.01) in men and from 0.43 to 0.63 (P < 0.01) in women. Compared with 24HR, FVS significantly (P < 0.05) overestimated intake at 2 of 4 sites for men and all 4 sites for women. Differences in estimated total servings of fruits and vegetables/d ranged from 0.16 to 3.06 servings. On average, the FVS overestimated intake by 1.76 servings in men and 2.11 servings in women. Alternative FVS scoring procedures and a 1-item screener lowered correlations with 24HR as well as serum carotenoids but alternate scoring procedures generally improved estimations of servings. [ABSTRACT FROM AUTHOR]