Julia K. Kolodziejczyk

Design and implementation of a randomized controlled social and mobile weight loss trial for young adults (project SMART)

PURPOSE To describe the theoretical rationale, intervention design, and clinical trial of a two-year weight control intervention for young adults deployed via social and mobile media. METHODS A total of 404 overweight or obese college students from three Southern California universities (M(age) = 22( ± 4) years; M(BMI) = 29( ± 2.8); 70% female) were randomized to participate in the intervention or to receive an informational web-based weight loss program. The intervention is based on behavioral theory and integrates intervention elements across multiple touch points, including Facebook, text messaging, smartphone applications, blogs, and e-mail. Participants are encouraged to seek social support among their friends, self-monitor their weight weekly, post their health behaviors on Facebook, and e-mail their weight loss questions/concerns to a health coach. The intervention is adaptive because new theory-driven and iteratively tailored intervention elements are developed and released over the course of the two-year intervention in response to patterns of use and user feedback. Measures of body mass index, waist circumference, diet, physical activity, sedentary behavior, weight management practices, smoking, alcohol, sleep, body image, self-esteem, and depression occur at 6, 12, 18, and 24 months. Currently, all participants have been recruited, and all are in the final year of the trial. CONCLUSION Theory-driven, evidence-based strategies for physical activity, sedentary behavior, and dietary intake can be embedded in an intervention using social and mobile technologies to promote healthy weight-related behaviors in young adults.

Reliability and validity of child/adolescent food frequency questionnaires that assess foods and/or food groups.

Objective: Summarize the validity and reliability of child/adolescent food frequency questionnaires (FFQs) that assess food and/or food groups. Methods: We performed a systematic review of child/adolescent (6–18 years) FFQ studies published between January 2001 and December 2010 using MEDLINE, Cochrane Library, PsycINFO, and Google Scholar. Main inclusion criteria were peer reviewed, written in English, and reported reliability or validity of questionnaires that assessed intake of food/food groups. Studies were excluded that focused on diseased people or used a combined dietary assessment method. Two authors independently selected the articles and extracted questionnaire characteristics such as number of items, portion size information, time span, category intake frequencies, and method of administration. Validity and reliability coefficients were extracted and reported for food categories and averaged across food categories for each study. Results: Twenty-one studies were selected from 873, 18 included validity data, and 14 included test-retest reliability data. Publications were from the United States, Europe, Africa, Brazil, and the south Pacific. Validity correlations ranged from 0.01 to 0.80, and reliability correlations ranged from 0.05 to 0.88. The highest average validity correlations were obtained when the questionnaire did not assess portion size, measured a shorter time span (ie, previous day/week), was of medium length (ie, ∼20–60 items), and was not administered to the childs parents. Conclusions: There are design and administration features of child/adolescent FFQs that should be considered to obtain reliable and valid estimates of dietary intake in this population.

Feasibility and effectiveness of an automated bilingual text message intervention for weight loss: pilot study.

Background Little is known about the feasibility and acceptability of tailored text message based weight loss programs for English and Spanish-language speakers. Objective This pilot study evaluated the feasibility, acceptability, and estimated impact of a tailored text message based weight loss program for English and Spanish-language speakers. The purpose of this pilot study was to inform the development of a full-scale randomized trial. Methods There were 20 overweight or obese participants (mean age 40.10, SD 8.05; 8/20, 40% male; 9/20, 45% Spanish-speakers) that were recruited in San Diego, California, from March to May 2011 and evaluated in a one-group pre/post clinical trial. For 8 weeks, participants received and responded to 3-5 text messages daily sent from a fully automated text messaging system. They also received printed weight loss materials and brief 10-15 minute weekly counseling calls. To estimate the impact of the program, the primary outcome was weight (kg) measured during face-to-face measurement visits by trained research staff. Pre and post differences in weight were analyzed with a one-way repeated measures analysis of variance. Differences by language preference at both time points were analyzed with t tests. Body mass index and weight management behaviors also were examined. Feasibility and acceptability were determined by recruitment success, adherence (ie, percentage of replies to interactive text messages and attrition), and participant satisfaction. Results Participants who completed the final assessment (N=18) decreased body weight by 1.85 kg (F 1,17=10.80, P=.004, CI∆ 0.66-3.03, η2=0.39). At both time points, there were no differences in weight by language preference. Participants responded to 88.04% (986/1120) of interactive text messages, attrition rate was 10% (2/20), and 94% (19/20) of participants reported satisfaction with the program. Conclusions This fully automated text message based weight program was feasible with English and Spanish-speakers and may have promoted modest weight loss over an 8-week period. Trial Registration Clinicaltrials.gov NCT01171586; http://clinicaltrials.gov/ct2/show/NCT01171586 (Archived by WebCite at http://www.webcitation.org/6Ksr6dl7n).

Relationships between depression, gender, and unhealthy weight loss practices among overweight or obese college students.

INTRODUCTION Unhealthy weight loss practices are common among female college students. It is unknown if these practices are also most common among women in the subset of overweight or obese college students or if these practices are related to depression. We examined the relationship between gender, depression, and unhealthy weight loss practices among overweight or obese college students. METHODS Students (body mass index between 25.0 and 34.9 kg/m(2)) from three Southern California universities (M(age) = 22 years, SD = 4; 70% women) were recruited from May 2011 to May 2012 for participation in a weight loss clinical trial (N = 404). Logistic regressions were performed with baseline data to assess the cross-sectional relationship between self-reported unhealthy weight loss practices and gender and depression as measured by the Center for Epidemiologic Studies Depression short form. RESULTS Twenty-nine percent of participants reported engaging in at least one unhealthy weight loss behavior (e.g., fasting, purging) over the last 30 days, with no differences by gender. Self-report of at least one unhealthy weight loss behavior was associated with report of symptoms of depression (e(B) = 1.14 [confidence interval, CI: 1.08-1.20]), adjusting for potential confounders. Interactions between gender and depression were not significant (e(B) = 1.04 [CI: 0.93-1.16]). CONCLUSION Among an overweight or obese sample of college students, unhealthy weight loss practices were equally common in both genders, and students with depressive symptomatology were at greatest risk. Obesity interventions targeting overweight or obese college students should educate both men and women about the dangers of unhealthy weight loss practices. In addition, screening for depression can help identify students who would benefit from additional supportive and coping strategies and resources.

Outcomes of a 1‐year randomized controlled trial to evaluate a behavioral ‘stepped‐down’ weight loss intervention for adolescent patients with obesity

Stepped‐care approaches to weight loss have shown some success among adults. A ‘stepped‐down’ version of the stepped‐care approach to adolescent weight loss has never been evaluated.

Reliability and concurrent and construct validity of the Strategies for Weight Management measure for adults

INTRODUCTION This study evaluates the reliability and validity of the strategies for weight management (SWM) measure, a questionnaire that assesses weight management strategies for adults. The SWM includes 20 items that are categorized within the following subscales: (1) energy intake, (2) energy expenditure, (3) self-monitoring, and (4) self-regulation. METHODS Baseline and 6-month data were collected from 404 overweight/obese adults (mean age=22±3.8 years, 68% ethnic minority) enrolled in a randomized controlled trial aiming to reduce weight by improving diet and physical activity behaviours. Reliability and validity were assessed for each subscale separately. Cronbach alpha was conducted to assess reliability. Concurrent, construct I (sensitivity to the study treatment condition), and construct II (relationship to the outcomes) validity were assessed using linear regressions with the following outcome measures: weight, self-reported diet, and weekly energy expenditure. RESULTS All subscales showed strong internal consistency. The strength of the validity evidence depended on subscale and validity type. The strongest validity evidence was concurrent validity of the energy intake and energy expenditure subscales; construct I validity of the energy intake and self-monitoring subscales; and construct II validity of the energy intake, energy expenditure, and self-regulation subscales. CONCLUSIONS Results indicate that the SWM can be used to assess weight management strategies among an ethnically diverse sample of adults as each subscale showed evidence of reliability and select types of validity. As validity is an accumulation of evidence over multiple studies, this study provides initial reliability and validity evidence in one population segment.

Exploratory and Confirmatory Factor Analyses and Demographic Correlate Models of the Strategies for Weight Management Measure for Overweight or Obese Adults

Purpose. There is a need for a self-report measure that assesses use of recommended strategies related to weight management. Design. Cross-sectional analysis. Setting. Universities, community. Subjects. Exploratory factor analysis (EFA) involved data from 404 overweight/obese young adults (mean age = 22 years, 48% non-Hispanic white, 68% ethnic minority). Confirmatory factor analysis (CFA) involved data from 236 overweight/obese adults (mean age = 42 years, 63% non-Hispanic white, 84% ethnic minority). Measures. The Strategies for Weight Management (SWM) measure is a 35-item questionnaire that assesses use of recommended behavioral strategies for reducing energy intake and increasing energy expenditure in overweight/obese adults. Analysis. EFA and CFA were conducted on the SWM. Correlate models assessed the associations between SWM factor/total scores and demographics by using linear regressions. Results. EFA suggested a four-factor model: strategies categorized as targeting (1) energy intake, (2) energy expenditure, (3) self-monitoring, and (4) self-regulation. CFA indicated good model fit (χ2/df=2.0, comparative fit index = .90, standardized root mean square residual = .06, and root mean square error of approximation = .07, confidence interval = .06–.08, R2 = .11–.74). The fourth factor had the lowest loadings, possibly because the items cover a wide domain. The final model included 20 items. Correlate models revealed weak associations between the SWM scores and age, gender, Hispanic ethnicity, and relationship status in both samples, with the models explaining only 1% to 8% of the variance (betas = –.04 to .29, p < .05). Conclusion. The SWM has promising psychometric qualities in two diverse samples.

Associations of soluble fiber, whole fruits/vegetables, and juice with plasma Beta-carotene concentrations in a free-living population of breast cancer survivors.

Objective: Soluble fiber and the physical state of fruits/vegetables affect plasma ß-carotene concentrations; however, most of this research was conducted in laboratory-based settings. These analyses investigated the relationship between soluble fiber and juiced versus whole fruits/vegetables to plasma ß-carotene concentrations in a free-living population. Method: This cross-sectional analysis used 12-month follow-up data from the Womens Healthy Eating & Living Study (1995–2006), a study to improve diet in breast cancer survivors in the Western United States. The dietary nutrients considered in this analysis included intake of soluble fiber (g), ß-carotene from fruit/vegetable juice (mg), and ß-carotene from whole fruits/vegetables (mg). A linear regression model was used to assess the relationship of the variables to plasma ß-carotene concentrations. Results: Out of 3,088 women enrolled in the Womens Healthy Eating & Living Study, 2,397 women had complete data (mean age = 54). The final model accounted for approximately 49% of the explained variance in plasma ß-carotene concentrations. Fruit/vegetable juice had the largest positive relation to plasma ß-carotene concentrations (standardized parameter estimate = 0.23, p < 0.01), followed by whole fruits/vegetables (standardized parameter estimate = 0.09, p < 0.01). Conclusion: Soluble fiber may inhibit ß-carotene absorption; therefore, consumption of juice may increase plasma ß-carotene concentrations more than whole fruits/vegetables in free-living populations.

Strategies that predict weight loss among overweight/obese young adults.

OBJECTIVES Understanding the characteristics of young adults who have difficulty achieving a healthy weight may help develop more effective interventions. METHODS Signal detection was conducted to identify subgroups of overweight/obese young adults more or less likely to lose weight (5% weight loss) over 6 months. Data were collected from a diverse sample involved in a randomized controlled behavioral weight loss intervention (N = 404). RESULTS Overall, 15% (N = 57) of participants achieved <5% weight loss. Change in self-monitoring weight, baseline score of gym attendance/participating in exercise classes, and change in eating less fat were the best predictors of weight loss. CONCLUSION These strategies may be particularly helpful to promote short-term weight loss in overweight/obese young adults.