Computerized advice on drug dosage to improve prescribing practice

Background Maintaining therapeutic concentrations of drugs with a narrow therapeutic window is a complex task. Several computer systems have been designed to help doctors determine optimum drug dosage. Significant improvements in health care could be achieved if computer advice improved health outcomes and could be implemented in routine practice in a cost effective fashion. This is an updated version of an earlier Cochrane systematic review, by Walton et al, published in 2001. Objectives To assess whether computerised advice on drug dosage has beneficial effects on the process or outcome of health care. Search strategy We searched the Cochrane Effective Practice and Organisation of Care Group specialized register (June 1996 to December 2006), MEDLINE (1966 to December 2006), EMBASE (1980 to December 2006), hand searched the journal Therapeutic Drug Monitoring (1979 to March 2007) and the Journal of the American Medical Informatics Association (1996 to March 2007) as well as reference lists from primary articles. Selection criteria Randomized controlled trials, controlled trials, controlled before and after studies and interrupted time series analyses of computerized advice on drug dosage were included. The participants were health professionals responsible for patient care. The outcomes were: any objectively measured change in the behaviour of the health care provider (such as changes in the dose of drug used); any change in the health of patients resulting from computerized advice (such as adverse reactions to drugs). Data collection and analysis Two reviewers independently extracted data and assessed study quality. Main results Twenty-six comparisons (23 articles) were included (as compared to fifteen comparisons in the original review) including a wide range of drugs in inpatient and outpatient settings. Interventions usually targeted doctors although some studies attempted to influence prescriptions by pharmacists and nurses. Although all studies used reliable outcome measures, their quality was generally low. Computerized advice for drug dosage gave significant benefits by: 1. increasing the initial dose (standardised mean difference 1.12, 95% CI 0.33 to 1.92) 2. increasing serum concentrations (standradised mean difference 1.12, 95% CI 0.43 to 1.82) 3. reducing the time to therapeutic stabilisation (standardised mean difference -0.55, 95% CI -1.03 to -0.08) 4. reducing the risk of toxic drug level (rate ratio 0.45, 95% CI 0.30 to 0.70) 5. reducing the length of hospital stay (standardised mean difference -0.35, 95% CI -0.52 to -0.17). Authors' conclusions This review suggests that computerized advice for drug dosage has some benefits: it increased the initial dose of drug, increased serum drug concentrations and led to a more rapid therapeutic control. It also reduced the risk of toxic drug levels and the length of time spent in the hospital. However, it had no effect on adverse reactions. In addition, there was no evidence to suggest that some decision support technical features (such as its integration into a computer physician order entry system) or aspects of organization of care (such as the setting) could optimise the effect of computerised advice.