What is missing from descriptions of treatment in trials and reviews?

I would echo the authors' call for more details from trials to help replicate non-pharmacological treatments in practice. I would go further to remind the readers that even with trials involving pharmacological treatments, there is often missing information that hamper the implementation of new treatments. As a pharmacist, I often come across two common areas that require further clarification. First, dose adjustment for impaired clearancc or adverse effects is often not described in details. For example, gemcitabine is mainly renally excreted and the manufacturer provides no dosing recommendation. So how is its dose adjusted in the clinical trials? When contacted, some primary investigators would reply that no adjustment was used while others might say that it was left to the individual centres.

The second common missing information relates to pharmaceutical preparation. For example, intraperitoneal paclitaxel or cisplatin ovarian cancer is diluted in 2 litres of warmed normal saline (Armstrong N Engl J Med 2006). How warm is warm? Would the rise in temperature affect the physicochemical stability of the solution? Intravesical interferon with BCG is used for superficial bladder cancer (O'Donnell J Urol 2001; Lam Urol Oncol 2003). How are these drugs mixed together and what is the stability of the mixture? As it happens, some interferon preparations contain antibacterial preservative which can destroy the potency of the BCG. Similarly, information is often sketchy with drug treatment administered by intrathecal route. We reviewed 44 reports of clinical trials involving intrathecal chemotherapy and found only 24 described which diluent and volume was used, even though the type of diluent and drug concentration may affect its pH and osmolality, both of which may have implications of the safety of intrathecal administration.

Competing interests: None declared