Do randomized controlled trials discuss healthcare costs?

Healthcare costs, particularly pharmaceutical costs, are a dominant issue for most healthcare organizations, but it is unclear if randomized controlled trials (RCTs) routinely discuss costs. Our objective was to assess the frequency and factors associated with the inclusion of costs in RCTs.

We randomly sampled 188 RCTs spanning three years (2003-2005) from six high impact journals. The sample size for RCTs was based on a calculation to estimate the inclusion of actual drug costs with a precision of +/-3%. Two reviewers independently extracted cost data and study characteristics. Frequencies were calculated and potential characteristics associated with the inclusion of costs were explored. Actual drug costs were included in 4.7% (9/188) of RCTs; any actual costs were included in 7.4% (14/188) of RCTs; and any mention of costs was included in 27.7% (52/188) of RCTs. As the amount of industry funding increased across RCTs, from non-profit to mixed to fully industry funded RCTs, there was a statistically significant reduction in the number of RCTs with any actual costs (Cochran-Armitage test, p = 0.005) and any mention of costs (Cochran-Armitage test, p = 0.02). Logistic regression analysis also indicated funding was associated with the inclusion of any actual cost (OR = 0.34, p = 0.009) or any mention of costs (OR = 0.63, p = 0.02). Journal, study conclusions, study location, primary author's country and product age were not associated with inclusion of cost information.

While physicians are encouraged to consider costs when prescribing drugs for their patients, actual drug costs were provided in only 5% of RCTs and were not mentioned at all in 72% of RCTs. Industry funded trials were less likely to include cost information. No other factors were associated with the inclusion of cost information.