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. 2019 Aug 26;16:100441.
doi: 10.1016/j.conctc.2019.100441. eCollection 2019 Dec.

Systematic Review on the Quality of Randomized Controlled Trials From Saudi Arabia

Free PMC article

Systematic Review on the Quality of Randomized Controlled Trials From Saudi Arabia

Ahmad Mamoun Rajab et al. Contemp Clin Trials Commun. .
Free PMC article


Background: The quality of randomized controlled trials from Saudi Arabia is unknown since most are observational studies.

Objective: To determine (1) the quantity and quality of randomized controlled trials published from Saudi Arabia, and (2) whether significance of intervention effect varied by study quality.

Methods: PubMed, SCOPUS, and Cochrane were searched with keywords for trials published from Saudi Arabia until February 2018. A total of 422 records were identified and screened, resulting in 61 eligible trials for analysis. Two researchers abstracted trial characteristics and assessed quality in seven domains (randomization, allocation concealment, blinding of assessors or participants, incomplete outcome data, selective reporting, and other sources of bias) using the Cochrane Collaboration Risk of Bias Tool.

Results: A majority of the trials (57%) were published during 2010-2018. High risk of bias was present for blinding (outcome: 13%; participants and personnel: 28%). Biases could not be assessed due to lack of information (unclear risk) in the domains of randomization (54%), allocation concealment (44%), and blinding of outcome assessment (57%). When all seven domains were considered together (summary risk of bias), 0% of the trials had low risk, 39% had high risk, and 61% had unclear risk of biases. A greater proportion of high-risk trials had significant intervention effect than unclear-risk trials (79% vs. 67%).

Conclusion: The volume and quality of trials in Saudi Arabia was low. More high-quality randomized controlled trials are warranted to address chronic diseases.

Keywords: ANZCTR, Australian New Zealand Clinical Trial Registry; CCRBT; CCRBT, Cochrane Collaboration Risk of Bias Tool; CONSORT, Consolidated Standards of Reporting Trials; ISRCTN, International Standard Randomised Controlled Trials Number; RCT, randomized controlled trial; Randomized controlled trial; Research quality; Saudi Arabia.


Fig. 1
Fig. 1
Flow chart of study eligibility among randomized controlled trials in Saudi Arabia (KSA) from 1987 to 2018 (n = 61).
Fig. 2
Fig. 2
Time trend of randomized controlled trials published in Saudi Arabia from 1987 to 2018 (n = 61).
Fig. 3
Fig. 3
Proportion of trials with significant effects according to summary risk of bias – all trials published in Saudi Arabia from 1987 to 2018 (n = 61).

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