Public access to protocols of contemporary cancer randomized clinical trials

Abstract

Access to randomized clinical trial (RCT) protocols is necessary for the interpretation and reproducibility of the study results, but protocol availability has been lacking. We determined the prevalence of protocol availability for all published cancer RCTs in January 2020. We found that only 36.1% (48/133) of RCTs had an accessible protocol and only 11.3% of RCTs (15/133) had a publicly accessible protocol that was not behind a paywall. Only 18.0% (24/133) of RCTs were published in conjunction with the protocol on the journal website. In conclusion, few cancer RCTs have an accessible research protocol. Journals should require publication of RCT protocols along with manuscripts to improve research transparency.

Access to unpublished protocols and statistical analysis plans of randomised trials

“…These findings indicate that our approach of contacting authors was an ineffective method of obtaining access to protocols and SAPs. This is concerning, as many trials do not have a publicly available protocol or SAP [ 16 , 18 , 21 , 24 ], and so, for a large portion of trials, it is impossible for readers to identify whether authors have followed pre-planned methods, or whether they deviated in order to obtain more favourable results. Although authors are required to upload information about their trials to trial registry websites such as clinicaltrials.gov , the EU clinical trials register, or the ISRCTN registry, these registries provide very limited information compared to study protocols or SAPs.…”

“…These findings indicate that our approach of contacting authors was an ineffective method of obtaining access to protocols and SAPs. This is concerning, as many trials do not have a publicly available protocol or SAP [16,18,21,24], and so, for a large portion of trials, it is impossible for readers to identify whether authors have followed pre-planned methods, or whether they deviated in order to obtain more favourable results.…”

“…Trial protocols and statistical analysis plans (SAPs) provide a blueprint for how a study is to be conducted and analysed. Explicit description of such methods before the trial begins helps to identify and deter inappropriate changes made to study methods that could introduce bias, such as changes to outcomes [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] or statistical methods [4,10,[17][18][19][20][21][22][23], after preliminary examination of study results. Protocols and SAPs require more detail than other sources, such as trial registry websites, particularly around planned statistical methods, and are thus essential to enable critical appraisal of trial results.…”

How do trial teams plan for retention during the design stage of the trial? A scoping review protocol

“…Having a protocol that is incomplete and non-transparent makes it difficult to critically appraise the trial [ 1 ]. Protocols are needed for the readers of the corresponding paper to be able to fully appraise and interpret the results of the trial [ 2 ]. As per the 2013 SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) definition, a protocol is “a document that provides sufficient detail to enable understanding of the background, rationale, objectives, study population, interventions, methods, statistical analyses, ethical considerations, dissemination plans, and administration of the trial, replication of key aspects of trial methods and conduct; and appraisal of the trial’s scientific and ethical rigour from ethics approval to dissemination of results” (3;202).…”

“…However, this is not always the case, and some protocol publications will require payment for access. For example, of the cancer clinical trials published in January of 2020 ( n = 113), only 11.3% had a publicly accessible protocol that was not behind a paywall [ 2 ]. This further limits transparency and hinders replication in trial methods and conduct, which has been recommended for trial retention strategies in order to improve the evidence base for their effectiveness [ 6 ].…”