Reporting of methodologic information on trial registries for quality assessment: a study of trial records retrieved from the WHO search portal

Background: Although randomized clinical trials (RCTs) are considered the gold standard of evidence, their reporting is often suboptimal. Trial registries have the potential to contribute important methodologic information for critical appraisal of study results. Methods and Findings: The objective of the study was to evaluate the reporting of key methodologic study characteristics in trial registries. We identified a random sample (n = 265) of actively recruiting RCTs using the World Health Organization International Clinical Trials Registry Platform (ICTRP) search portal in 2008. We assessed the reporting of relevant domains from the Cochrane Collaboration’s ‘Risk of bias’ tool and other key methodological aspects. Our primary outcomes were the proportion of registry records with adequate reporting of random sequence generation, allocation concealment, blinding, and trial outcomes. Two reviewers independently assessed each record. Weighted overall proportions in the ICTRP search portal for adequate reporting of sequence generation, allocation concealment, blinding (including and excluding open label RCT) and primary outcomes were 5.7% (95% CI 3.0–8.4%), 1.4% (0–2.8%), 41% (35–47%), 8.4% (4.1–13%), and 66% (60–72%), respectively. The proportion of adequately reported RCTs was higher for registries that used specific methodological fields for describing methods of randomization and allocation concealment compared to registries that did not. Concerning other key methodological aspects, weighted overall proportions of RCTs with adequately reported items were as follows: eligibility criteria (81%), secondary outcomes (46%), harm (5%) follow-up duration (62%), description of the interventions (53%) and sample size calculation (1%). Conclusions: Trial registries currently contain limited methodologic information about registered RCTs. In order to permit adequate critical appraisal of trial results reported in journals and registries, trial registries should consider requesting details on key RCT methods to complement journal publications. Full protocols remain the most comprehensive source of methodologic information and should be made publicly available.

Uruguayn ja Argentiinan sellutehdaskonflikti latinalaisamerikkalaisena maa- ja metsäkiistana

English abstract: The pulp investment conflict of Argentina and Uruguay as a Latin American land and forest dispute

Valtiotoimijuudesta valtiollisiin toimijuuksiin : kriittisiä huomioita kansainvälisen politiikan tutkimuksen perusteista

English abstract: Critical reflections on the state-agent thesis in IR

Antikoloniaalisen vapautuksen yhteiskuntafilosofia: tapaus Frantz Fanon

English abstract: Anticolonial theory of liberation: case Frantz Fanon

Kansainvälisen politiikan opetus Suomessa1970- ja 1980-lukujen taitteessa : Morgenthaun realistisen opetusfilosofian näkökulma

English abstract: Teaching international relations in Finland : perspective of Morgenthau's realistic philosophy of education

Kansainvälinen politiikka "käytännöllisten ratkaisujen joukkona" : pragmatistinen tulkinta kansainvälisen politiikan tieteenalan itsekuvasta

English abstract: International relations (IR) as "collection of practical solutions" - pragmatist interpretation of the self-image of the discipline

Feministisen tutkimuksen ja valtavirran sukulaisuussuhteet kansanivälisen politiikan tieteenalalla

English abstract: Familiar relationships between feminist and mainstream IR