The effect of computers for weight loss: a systematic review and meta-analysis of randomized trials

Abstract

Background: The use of computers to deliver education and support strategies has been shown to be effective in a variety of conditions. We conducted a systematic review and meta-analysis to evaluate the impact of computer-based technology on interventions for reducing weight.

Methods: We searched MEDLINE, CENTRAL, CINAHL, PsycINFO, Google Scholar and ClinicalTrials.gov (all updated through June 2010) for randomized controlled trials evaluating the effect of computer-based technology on education or support interventions aimed at reducing weight in overweight or obese adults. We calculated weighted mean differences (WMD) and 95% confidence intervals (CI) using random effects models.

Results: Eleven trials with 13 comparisons met inclusion criteria. Based on six comparisons, subjects who received a computer-based intervention as an addition to the standard intervention given to both groups lost significantly more weight (WMD -1.48 kg, 95% CI -2.52, -0.43). Conversely, based on six comparisons, subjects for whom computer-based technology was substituted to deliver an identical or highly comparable intervention to that of the control group lost significantly less weight (WMD 1.47 kg, 95% CI 0.13, 2.81). Significantly different weight loss seen in "addition" comparisons with less than six months of follow-up (WMD -1.95 kg, 95% CI -3.50, -0.40, two comparisons) was not seen in comparisons with longer follow-up (-1.08 kg, 95% CI -2.50, 0.34, four comparisons). Analyses based on quality and publication date did not substantially differ.

Conclusions: While the addition of computer-based technology to weight loss interventions led to statistically greater weight loss, the magnitude (<1.5 kg) was small and unsustained.

Figure 1

Study selection flow diagram. RCT = randomized controlled trial.

Figure 2

Risk of bias summary for included studies. + Study has a low risk of bias. - Study has a high risk of bias. ? Unclear or uncertain risk of bias. See Appendix 5 for more information.

Figure 3

Overall change in weight (kg), subgrouped by methodological approach (addition versus substitution of computer-based intervention). Test for subgroup differences comparing "addition of computer "to "substitution of computer-all studies": p = 0.07. Test for subgroup differences comparing "addition of computer" to "substitution of computer-excluding Burnett": p = 0.0007. kg = kilograms, SD = standard deviation, IV = inverse variance, CI = confidence interval.

Figure 4

Overall change in weight (kg), restricted to studies that added a computer-based intervention, subgrouped by duration of the intervention. kg = kilograms, SD = standard deviation, IV = inverse variance, CI = confidence interval.

Figure 5

Overall change in weight (kg), restricted to studies that added a computer-based intervention, subgrouped by duration of the follow-up. kg = kilograms, SD = standard deviation, IV = inverse variance, CI = confidence interval.

Figure 6

Overall change in weight (kg), restricted to studies that added a computer-based intervention, subgrouped by the date of publication. kg = kilograms, SD = standard deviation, IV = inverse variance, CI = confidence interval.

Figure 7

Overall change in BMI (kg/m²), subgrouped by methodological approach (addition versus substitution of computer-based intervention). Test for subgroup differences: p = 0.30. BMI = body mass index, kg = kilograms, m = meters, SD = standard deviation, IV = inverse variance, CI = confidence interval.