TITLE: Longitudinal bidirectional  relations between  body dissatisfaction and depressive symptoms among Black adolescents: A cross-lagged panel analysis
AUTHORS: Yan Wang, Sarah D. Lynne, Dawn Witherspoon, Maureen M. Black

[DESCRIPTION]
<div class = "text-blocks"><div class = "text-block"><div class = "justify" style = "text-align:left">This protocol is </div></div><div class = "text-block"><div class = "justify" style = "text-align:left"><a href="" style = "text-decoration:underline;color:blue;cursor:pointer;"><span style = ":;">1) To compare body dissatisfaction and depressive symptoms by weight status (overweight/obesity vs. healthy weight) among Black adolescents 12-13 years old.</span></a></div></div><div class = "text-block"><div class = "justify" style = "text-align:left">2) To investigate the relationship between body dissatisfaction and depressive symptoms among Black adolescents 12-13 years old, who were overweight or obese.</div></div><div class = "text-block"><div class = "justify" style = "text-align:left">3) To investigate the relationship between body dissatisfaction and depressive symptoms among Black adolescents 12-13 years old, who were of healthy weight.</div></div></div>

[STEPS]
?. Purpose1) To compare body dissatisfaction and depressive symptoms by weight status (overweight/obesity vs. healthy weight) among Black adolescents 12-13 years old.2) To investigate the relationship between body dissatisfaction and depressive symptoms among Black adolescents 12-13 years old, who were overweight or obese.3) To investigate the relationship between body dissatisfaction and depressive symptoms among Black adolescents 12-13 years old, who were of healthy weight.Target variables:Body dissatisfaction: discrepancy between perceived and ideal body weight and shapeDepressive symptoms
?. Inclusion CriteriaA sample of adolescents in middle schools, who were recruited to participate in a random controlled trial on overweight/obesity prevention, promoting healthy diet and physical activity. The adolescents who were Black.The adolescents who were 12-13 years old at the first assessment (baseline)The adolescents who were healthy weight (5-85th BMI percentile) or overweight/obese (>=85thBMI percentile). Both sexes.
?. Exclusion Criteria1)The adolescents who were not Black2)The adolescents who were younger than 12 years or older than 13 years at baseline3)The adolescents who were underweight (
?. Study DesignLongitudinal with three assessments: baseline (T1, 7/1/2002-4/16/2004), ~10 months (T2, 12/2/2002-11/4/2005) and ~24 months after baseline (T3, 2/3/2004-11/7/2006)
?. Study Participation and Patient Registration / Allocation Procedures(1) The obesity prevention intervention trial has been registered with the Clinical Trials Registry. (ClinicalTrials.gov Identifier: NCT00746083).(2) The University of Maryland Baltimore Institutional Review Board approved this research; (3) All parents signed informed consent, and all adolescents signed informed assent.
?. Surveys / QuestionnairesData on socio-demographic characteristics, body dissatisfaction and depressive symptoms were collected through computerized audio computer-assisted self-interview (ACASI).
?. MeasuresAdolescent characteristicsSex, age, race/ethnicity, height, body weight, birthdate, poverty, maternal education, maternal overweight/obesity and intervention status. Depressive symptomslDepressive symptoms were measured with the Beck Depression Inventory (BDI)lConsisting of 21 items relating to depressive symptoms in the past week, e.g., sadness, feeling guilty, and fatigue, using a 4-point response scale of severity.lA summary score was calculated with higher scores indicating more depressive symptoms.Body dissatisfactionlBody dissatisfaction was measured by comparing perceived body image with ideal image, using a culturally adapted, age- and sex-specific, 9-point silhouette scale, modified from Stunkard, Sørensen, & Schulsinger, (1983) to more closely resemble Black youth. lThe silhouettes were ordered from thinnest (rating=1) to heaviest (rating=9). The adolescents identified the silhouette closest to their current body size and then on a separate, but identical scale, the silhouette they desired.lThe discrepancy score was defined as perceived body size minus desired body size, with a positive discrepancy score indicating desire for a thinner body and a negative score indicating desire to be heavier.
?. AnalysisT-test for continuous variable and Chi-square tests (or Fisher’s exact test) for categorical variable by weight statusPearson correlation coefficients among body dissatisfaction and depressive symptoms over time and the covariates. Trend test for change of body dissatisfaction and depressive symptoms over timeCross-lagged panel model (CLPM) to examine the reciprocal relations between body dissatisfaction and depressive symptoms, accounting for the stability of depressive symptoms or body dissatisfaction across time.