Table 12Risk of bias–haloperidol versus quetiapine

StudyItemJudgmentDescription
Arvantis et al. 199746Adequate sequence generation?UNCLEARReported as a randomized trial, with no further details regarding sequence generation in trial report.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in trial report.
Blinding?UNCLEARReported as a DB trial, with no further details regarding blinding.
Incomplete outcome data addressed?YESITT principle not used, but 99% of participants included in the analyses.
Free of selective reporting?YESProtocol is not available, but outcomes in the methods and results match.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Atmaca et al. 200247Adequate sequence generation?UNCLEARReported as a randomized trial, with no futher details regarding sequence generation.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in the trial report.
Blinding?UNCLEARThis study was not reported as blinded, and there was not reporting of any blinding.
Incomplete outcome data addressed?UNCLEARReported that all participants completed the study.
Free of selective reporting?YESProtocol not available, but outcomes in methods and results match.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Copolov et al. 200068Adequate sequence generation?UNCLEARReported as a randomized trial, with no futher details regarding sequence generation.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in the trial report.
Blinding?UNCLEARReported as a DB trial, with no futher details regarding blinding.
Incomplete outcome data addressed?NOITT principle not used and attrition rate was high with 33% of participants dropping out from the trial.
Free of selective reporting?YESOutcomes is the method section match with the results.
Free of other bias?UNCLEARBaseline characteristics were similar, with the exception for differences in the subgroup diagnoses of schizoprhenia and AIMS scores. Other sources of bias were not detected.
Davidson et al. 200975Adequate sequence generation?YESReported the use of a centralized computerized online randomization system.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in trial report.
Blinding?NOReported as an open-label trial.
Incomplete outcome data addressed?NOITT principle was not used, and attrition was high, with 43% of participants not completing the trial.
Free of selective reporting?YESProtocol is not available, but outcomes in the methods and results match.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Emsley et al. 200079Adequate sequence generation?UNCLEARReported as a randomized trial, with no further details regarding sequence generation in trial report.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in trial report.
Blinding?UNCLEARReported as a DB trial, with no further details regarding blinding.
Incomplete outcome data addressed?YESModified ITT using LOCF on those who received drug and had at least one followup observation. 98% analyzed.
Free of selective reporting?YESProtocol is not available, but outcomes in the methods and results match.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Emsley et al. 200580Adequate sequence generation?UNCLEARReported as a randomized trial, with no further details regarding sequence generation.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in the trial report.
Blinding?UNCLEARReported as investigator-blinded trial. No other details about blinding.
Incomplete outcome data addressed?YES47 randomized; 33 analyzed; ITT reported (70% completion).
Free of selective reporting?YESOutcomes in method section are matched to the results.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Glick et al. 200565Adequate sequence generation?UNCLEARReported as a randomized trial, with no further details regarding sequence generation.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in trial report.
Blinding?NOReported as an open-label trial.
Incomplete outcome data addressed?NOITT principle was not used, and attrition rate was high, with 66% of participants not available at the end of the trial.
Free of selective reporting?YESProtocol is not available, but outcomes in the methods and results match.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Kahn et al. 200891Adequate sequence generation?YESTrial reported patients were randomly assigned by a dedicated web-based online system developed inhouse by the Data Management Department of the Julius Center for Health Sciences and Primary Care.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in trial report.
Blinding?NOReported as an open-label trial. Patients and their treating psychiatrists were unmasked for the assigned treatment.
Incomplete outcome data addressed?YES498 randomized. 498 analyzed. ITT reported. 342 completed followup.
Free of selective reporting?YESProtocol is not available, but outcomes in the methods and results match.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
McCue et al. 200673Adequate sequence generation?YESReported that randomization was performed using a website-based randomization scheme (www​.randomization.com).
Allocation concealment?YESReported that the hospital staff with no clinical responsibilities and no knowledge of the patients oversaw the assignment procedure and assigned medications in sequential order, strictly following the randomized list. Also reported that the treating psychiatrist did not have access to this list.
Blinding?NOReported as an open-label study with both the patient and the treating psychiatrist being aware of the antipsychotic being prescribed.
Incomplete outcome data addressed?YESITT principle not used during the analysis, but 98% of randomized participants analyzed.
Free of selective reporting?YESProtocol is not available, but outcomes in the methods and results match.
Free of other bias?UNCLEARReported that there was a significant difference in the age of participants among the 6 treatment groups and a significantly different proportion of patients received additional medications. Other sources of bias were not detected.
Purdon et al. 2001123Adequate sequence generation?UNCLEARReported as a randomized trial, with no further details regarding sequence generation.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in the trial report.
Blinding?UNCLEARReported as a DB trial, with no further details regarding blinding.
Incomplete outcome data addressed?UNCLEARUnequal dropout between groups. Analyses included a range of 84% to 100% of patients.
Free of selective reporting?YESProtocol was not available, but outcomes in the methods and results are similar.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.
Velligan et al. 2002143Adequate sequence generation?UNCLEARReported as a randomized trial, with no further details regarding sequence generation.
Allocation concealment?UNCLEARNo information reported regarding allocation concealment in the trial report.
Blinding?UNCLEARReported as a DB trial, with no further details regarding blinding.
Incomplete outcome data addressed?UNCLEARThis is a substudy analysing 58/116 (50%) of eligible patients and excluded dropouts.
Free of selective reporting?YESProtocol was not available, but outcomes in the methods and results are similar.
Free of other bias?YESNo significant differences in baseline characteristics or other sources of bias detected.

AIMS = Abnormal Involuntary Movement Scale; DB = double-blind; ITT = intention-to-treat analysis; LOCF = last observation carried forward

From: Appendix E, Risk of Bias Assessment for Randomized Controlled Trials and Nonrandomized Controlled Trials

Cover of First-Generation Versus Second-Generation Antipsychotics in Adults: Comparative Effectiveness
First-Generation Versus Second-Generation Antipsychotics in Adults: Comparative Effectiveness [Internet].
Comparative Effectiveness Reviews, No. 63.
Abou-Setta AM, Mousavi SS, Spooner C, et al.

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