Methodological quality of behavioural weight loss studies: a systematic review.

This systematic review assessed the methodological quality of behavioural weight loss intervention studies conducted among adults and associations between quality and statistically significant weight loss outcome, strength of intervention effectiveness and sample size. Searches for trials published between January, 2009 and December, 2014 were conducted using PUBMED, MEDLINE and PSYCINFO and identified ninety studies. Methodological quality indicators included study design, anthropometric measurement approach, sample size calculations, intent-to-treat (ITT) analysis, loss to follow-up rate, missing data strategy, sampling strategy, report of treatment receipt and report of intervention fidelity (mean = 6.3). Indicators most commonly utilized included randomized design (100%), objectively measured anthropometrics (96.7%), ITT analysis (86.7%) and reporting treatment adherence (76.7%). Most studies (62.2%) had a follow-up rate > 75% and reported a loss to follow-up analytic strategy or minimal missing data (69.9%). Describing intervention fidelity (34.4%) and sampling from a known population (41.1%) were least common. Methodological quality was not associated with reporting a statistically significant result, effect size or sample size. This review found the published literature of behavioural weight loss trials to be of high quality for specific indicators, including study design and measurement. Identified for improvement include utilization of more rigorous statistical approaches to loss to follow up and better fidelity reporting.

Weight loss following a clinic-based weight loss program among adults with attention deficit/hyperactivity disorder symptoms.

OBJECTIVE: The purpose of the present study was to compare obese patients screening positive or negative for attention deficit/hyperactivity disorder (ADHD) on pretreatment body mass index (BMI), weight loss following a 16 week clinic-based behavioral weight loss program, weight loss attempts, dietary and physical activity habits, perceived difficulty of weight control skills, and eating self-efficacy. DESIGN: Patients who completed a behavioral weight loss program were approached to complete questionnaires on ADHD and eating habits. Medical charts were reviewed to obtain weight at pre- and post-treatment. RESULTS: Participants (N=63) were 75% female, mean age was 49 (SD=10.3), mean body mass index (BMI) was 41.4 kg/m² (SD=6.8) and 30% screened positive for ADHD on the Adult ADHD Symptom Rating Scale. Participants screening positive for ADHD did not have a higher BMI at baseline (p=0.41), but reported more previous weight loss attempts (p=0.01) and lost less weight (p=0.02) than participants who screened negative. Participants screening positive also reported consuming fast food meals more frequently (p=0.04), higher levels of emotional eating (p=0.002), greater difficulty with weight control skills (p=0.01), and lower eating self-efficacy (p=0.001). CONCLUSION: Attention-related problems appear to be common among weight treatment-seeking samples and represent a significant barrier to weight control that has not yet been addressed in the literature.

PDA-assisted low glycemic index dietary intervention for type II diabetes: a pilot study.

BACKGROUND: Epidemiological and dietary intervention studies suggest that a low-glycemic index (GI) diet is beneficial for blood glucose control; however, long-term clinical utility of the low GI diet has not been fully investigated. OBJECTIVES: To evaluate the feasibility and efficacy of a nutritionist-delivered low-GI dietary intervention, with the support of a personal digital assistant (PDA), for adult patients with poorly controlled type II diabetes. METHOD: The low-GI intervention consisted of six counseling sessions and the use of a PDA-based food database with GI scores for 6 months. Study outcomes included feasibility measures, glycosylated hemoglobin levels (HbA1c), GI and glycemic load (GL) score of self-reported dietary intake, body weight, depression and quality of life (QOL). Measures were obtained at baseline, 3 and 6 months. RESULTS: Of 31 adult patients approached, 15 met study eligibility criteria and were enrolled in the study. Thirteen patients (87%) completed all study assessments. Findings included decreases in average HbA1c (-0.5% P = 0.02), body weight, hip circumference, blood pressure, dietary GI and daily caloric intake. Diabetes impact scores also decreased. All but one participant completed all components of the intervention. There were mixed reports regarding the usefulness of the PDAs; however, participants offered helpful suggestions for further development. CONCLUSIONS: Results of this pilot study support the feasibility of implementing a nutritionist-delivered, PDA-assisted low-GI dietary intervention for patients with poorly controlled type II diabetes. Encouraging initial efficacy data require further testing in the context of a randomized clinical trial.