Ward et al. BMC Public Health 2011, 11:431 http://www.biomedcentral.com/1471-2458/11/431 the Parenting Convergence Scale (PCS), which assesses the degree to which parents work together to tackle par- enting responsibilities and includes subscales for com- munication, conflict, and support [31,32]. Parent Feeding Practices Parent feeding style and beha- viors are assessed using a combination of items from existing instruments including: (1) the Caregiver’s Feed- ing Style Questionnaire (CFSQ), which assesses two dimensions of parent feeding - demandingness and responsiveness) [33]; (2) the Parental Feeding Style Questionnaire (PFSQ), which includes subscales for emotional feeding, instrumental feeding, prompting/ encouragement to eat, and control over eating [34]; and (3) nine subscales from the Comprehensive Feeding Practices Questionnaire (CFPQ), specifically those for child control, child involvement, parent modeling of healthy eating, parent monitoring of child intake, paren- tal pressure to eat, parent restriction for health, parent restriction for weight control, encouraging of balance and variety, and teaching about nutrition [35]. Parent Physical Activity-Related Practices Measures of parent practices specific to physical activity are not well developed; therefore, a tool was developed by investiga- tors based on an extensive literature review (unpub- lished data) and using items and scales taken or modified from existing instruments [36]. Items assess constructs such as indoor/outdoor rules, use of physical activity as a reward or punishment, monitoring, control, support, parent role-modeling, family activity, praise, encouragement, education, and use of screen time for distraction. Parent Motivation to Change Practices Given the inclusion of the Self-Determination Theory Framework in our conceptual model, measures of intrinsic/autono- mous motivation to change behavior are also assessed. Autonomous motivation to change is assessed with the Treatment Self-Regulation Questionnaires (TSRQ), which measures controlling vs. autonomous reasons an individual has for adopting certain healthy behaviors [37]. The original measure was modified for this study to ask parents why they would adopt more positive par- enting practices. Parents’ feelings of competence are assessed using three separate measures: one focusing on feelings of competency related to their role as a parent, and the last two focusing on feelings of competency spe- cific to helping their child meet dietary and physical activity recommendations. Additional measures include the Parenting Sense of Confidence (PSOC) scale, which assesses parents’ self-efficacy (competence, problem-sol- ving ability, and capability) and satisfaction (affective dimension reflecting frustration, anxiety, and motiva- tion) related to their role as a parent [38]; as well as the Parenting Self-Efficacy for Children’s Healthy Weight Behaviors (PSE-CHWB), an instrument developed by Page 7 of 9 investigators to assess parents’ self-efficacy for adopting parenting behaviors that will help their children meet dietary and physical activity guidelines and promote healthy weight gain. Additionally, parent feelings of relatedness (i.e., attachment, social integration, reassur- ance of worth, reliable alliance, guidance, and opportu- nity for nurturance) are assessed using a modified version of the Social Provisions Scale (SPS) [39,40]. Items were adapted for this study to ask specifically about social support for general parenting. Other variables Several other variables thought to be related to the primary constructs of interest are assessed, including parenting stress (Parenting Stress Index [41]), parent depressive symptoms (Center for Epidemiologic Studies Depression Scale [42]), and child behavior (Eyberg’s Child Behavior Inventory [43]), but will not be described in detail in this paper. Evaluation Descriptive statistics will be used to compare the demo- graphic characteristics of intervention and control arm participants at baseline - medians for continuous vari- ables and proportions for categorical variables. All statis- tical tests and exploratory and confirmatory factor analyses on the physical and parenting and child psy- chological measures will be performed with either SAS 9.2 (SAS Institute, Cary NC) and MPlus [44]. Statistical tests will be conducted using a two-tailed test with an alpha value set at 0.05. Intervention implementation will be described using process evaluation data based on Glasgow’s RE-AIM framework [45] and Kirkpatrick’s Training Evaluation Model [46]. An intention-to-treat approach will be used for the primary hypothesis: the comparison of the mean change difference in child percent body fat from baseline to post-intervention between intervention and control chil- dren. We expect that our intervention will be effective in producing an absolute difference in change in percent body fat of 2%-3% between the two arms at post-inter- vention (35 weeks), but power was calculated based on the less optimistic 2% and with a conservative two-sided test of significance. Discussion The Parenting SOS program offers an innovative approach to addressing healthy weight development in families with preschool-age children. The intervention is based on considerable formative and pilot research, and addresses general parenting as the gateway activity for parents to develop appropriate parenting skills for their children’s healthy eating and activity patterns. Respond- ing to our formative data, we developed a companion child program that offers our families support in making changes to current lifestyle practices. In addition to the