Article type
Year
Abstract
Background: Life-style changes are often recommended for prevention or treatment of the early stages of chronic conditions.
Objectives: To assess the quality of trials of life-style interventions which informed two national clinical guidelines.
Methods: Systematic review identified randomized controlled trials (RCTs), meeting pre-specified inclusion criteria, comparing life-style interventions with control interventions or no treatment in two clinical areas: hypertension (129 trials assessing blood pressure outcomes, enrolling 7,500 participants), osteoporosis (37 trials assessing fracture outcomes, enrolling 20,548 participants). For each trial, quality was assessed, endpoint data extracted, and missing data requested from authors.
Results: The quality of trial reports was poor - only 17%, 5% and 20% reported adequate randomization, concealment of allocation and blinding of outcome assessors respectively - and showed little improvement since the CONSORT (Consolidated Standards of Reporting Trials) Statement in 1996. For hypertension trials, follow up was short (median=15 weeks, range: 8 weeks - 5 years); for osteoporosis trials follow up was generally longer (median=2 years, range 34 weeks - 10 years). For hypertension, 20 (16%) trials had missing standard deviations for both final responses and changes from baseline; these trials were generally older, smaller and of poorer quality than other trials. Eight trials (5%) did not report numbers of participants randomized to each arm and 36 (22%) did not report loss to follow up. Overall reported loss to follow up was 10% in hypertension trials, varying from 3% to 39% between types of intervention, and 22% in the longer osteoporosis trials.
Conclusions: Despite the CONSORT Statement, reporting of trials of life-style interventions remains poor and such trials may introduce bias in estimated treatment effects. The short duration of many trials of life-style interventions yields little information relevant to the long-term care required for chronic conditions. Trials of life-style interventions need to be larger, longer and of better quality.
Objectives: To assess the quality of trials of life-style interventions which informed two national clinical guidelines.
Methods: Systematic review identified randomized controlled trials (RCTs), meeting pre-specified inclusion criteria, comparing life-style interventions with control interventions or no treatment in two clinical areas: hypertension (129 trials assessing blood pressure outcomes, enrolling 7,500 participants), osteoporosis (37 trials assessing fracture outcomes, enrolling 20,548 participants). For each trial, quality was assessed, endpoint data extracted, and missing data requested from authors.
Results: The quality of trial reports was poor - only 17%, 5% and 20% reported adequate randomization, concealment of allocation and blinding of outcome assessors respectively - and showed little improvement since the CONSORT (Consolidated Standards of Reporting Trials) Statement in 1996. For hypertension trials, follow up was short (median=15 weeks, range: 8 weeks - 5 years); for osteoporosis trials follow up was generally longer (median=2 years, range 34 weeks - 10 years). For hypertension, 20 (16%) trials had missing standard deviations for both final responses and changes from baseline; these trials were generally older, smaller and of poorer quality than other trials. Eight trials (5%) did not report numbers of participants randomized to each arm and 36 (22%) did not report loss to follow up. Overall reported loss to follow up was 10% in hypertension trials, varying from 3% to 39% between types of intervention, and 22% in the longer osteoporosis trials.
Conclusions: Despite the CONSORT Statement, reporting of trials of life-style interventions remains poor and such trials may introduce bias in estimated treatment effects. The short duration of many trials of life-style interventions yields little information relevant to the long-term care required for chronic conditions. Trials of life-style interventions need to be larger, longer and of better quality.