A review of RCTs in four medical journals to assess the use of imputation to overcome missing data in quality of life outcomes
Open Access
- 11 August 2008
- journal article
- research article
- Published by Springer Science and Business Media LLC in Trials
- Vol. 9 (1), 1-6
- https://doi.org/10.1186/1745-6215-9-51
Abstract
Randomised controlled trials (RCTs) are perceived as the gold-standard method for evaluating healthcare interventions, and increasingly include quality of life (QoL) measures. The observed results are susceptible to bias if a substantial proportion of outcome data are missing. The review aimed to determine whether imputation was used to deal with missing QoL outcomes. A random selection of 285 RCTs published during 2005/6 in the British Medical Journal, Lancet, New England Journal of Medicine and Journal of American Medical Association were identified. QoL outcomes were reported in 61 (21%) trials. Six (10%) reported having no missing data, 20 (33%) reported ≤ 10% missing, eleven (18%) 11%–20% missing, and eleven (18%) reported >20% missing. Missingness was unclear in 13 (21%). Missing data were imputed in 19 (31%) of the 61 trials. Imputation was part of the primary analysis in 13 trials, but a sensitivity analysis in six. Last value carried forward was used in 12 trials and multiple imputation in two. Following imputation, the most common analysis method was analysis of covariance (10 trials). The majority of studies did not impute missing data and carried out a complete-case analysis. For those studies that did impute missing data, researchers tended to prefer simpler methods of imputation, despite more sophisticated methods being available.Keywords
This publication has 31 references indexed in Scilit:
- Evaluation of software for multiple imputation of semi-continuous dataStatistical Methods in Medical Research, 2007
- Review: A gentle introduction to imputation of missing valuesJournal of Clinical Epidemiology, 2006
- Self management of arthritis in primary care: randomised controlled trialBMJ, 2006
- Randomised controlled trial of a short course of traditional acupuncture compared with usual care for persistent non-specific low back painBMJ, 2006
- Treatment of low back pain by acupressure and physical therapy: randomised controlled trialBMJ, 2006
- Long term outcomes from the IMPACT randomised trial for depressed elderly patients in primary careBMJ, 2006
- Review of guidelines and literature for handling missing data in longitudinal clinical trials with a case studyPharmaceutical Statistics, 2006
- Targets and self monitoring in hypertension: randomised controlled trial and cost effectiveness analysisBMJ, 2005
- Cognitive behaviour therapy in addition to antispasmodic treatment for irritable bowel syndrome in primary care: randomised controlled trialBMJ, 2005
- Randomised controlled trial to compare surgical stabilisation of the lumbar spine with an intensive rehabilitation programme for patients with chronic low back pain: the MRC spine stabilisation trialBMJ, 2005