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Real-World Evidence Generation
Published in Kelly H. Zou, Lobna A. Salem, Amrit Ray, Real-World Evidence in a Patient-Centric Digital Era, 2023
Joseph S. Imperato, Joseph P. Cook, Diana Morgenstern, Kim Gilchrist, Tarek A. Hassan, Jorge Saenz, Danute Ducinskiene
One of the factors that increases the internal validity of the study results, beside the randomization, is the blinding as part of the clinical trial design. Blinding in pRCTs is usually not feasible as a comparison of the new intervention versus the standard care will break this kind of blinding. Possible strategies to compensate for the unblinding is to focus on hard end points, use adjudicated committee and statisticians who are blinded during the trial conduct (Gamerman et al. 2019).
Critical appraisal of randomized clinical trials
Published in O. Ajetunmobi, Making Sense of Critical Appraisal, 2021
The blinding procedure needs to be clearly stated in the trial report. Clinicians and subjects should both be blind to the nature of treatment the subjects are receiving. Blinding is important as it reduces bias in the way that subjects report their symptoms and the way clinicians observe beneficial or harmful effects thereby ensuring that the groups remain similar in all aspects (except treatment) after baseline.
Investigating links between diet and health outcomes
Published in Geoffrey P. Webb, Nutrition, 2019
To reduce the risk of bias subjects, animal or human, are usually randomly allocated to control and experimental groups. Ideally, the person conducting the experiment should be unaware of which group any particular subject is in, especially when making outcome assessments. In many human trials, studies are conducted using a double-blind design i.e. neither the subject nor the researcher is aware of which treatment a subject is receiving until after the data has been collected. Blinding is increasingly being used as a way of reducing potential bias in other types of study.
Peer Interventions in Severe Mental Illnesses: A Systematic Review and its Relation to Occupational Therapy
Published in Occupational Therapy in Mental Health, 2023
Ivan Cano Prieto, Salvador Simó Algado, Gemma Prat Vigué
Following the protocol established by the Cochrane guide, all the studies analyzed present a correct explanation for the generation of random sequence. Eight studies had allocation concealment problems: they did not clearly describe the random selection process. In none of the interventions were differences found between groups. Regarding the blinding of the participants and the personnel involved in the studies, all studies show a risk of bias due to the need for informed consent. Eight of the 17 studies present a low risk of detection bias: PSWs and client are aware of the intervention. Many of the articles included were deficient in attrition bias: systematic differences between groups in withdrawals from a study; in six of them it is not clear how the problem was solved and only in one of them was it omitted. Finally, only two cases of reporting bias were observed: systematic differences between reported and unreported findings (Table 2).
A systematic review and meta‐analysis of maintenance treatment for psychotic depression
Published in Nordic Journal of Psychiatry, 2022
Ahmed Al-Wandi, Christoffer Holmberg, Mikael Landén, Axel Nordenskjöld
All included studies were deemed to be of high quality according to the Jadad scale (see Table 2). All studies described using computer-generated randomization, except for the study by Meyers et al., where the randomization method was not mentioned. Double-blinding was mentioned in the studies by Flint et al., Meyers et al., and Bingham et al. and in all these studies it was implied that neither the study participant nor the person doing the assessment could identify the intervention. The study by Navarro et al. was single-blinded (and thus 0 points was given for blinding). The study by Wijkstra et al. was blinded in the acute phase of the treatment but was unblinded during the maintenance phase. Complete data of withdrawal was presented in the studies by Flint et al., Wijkstra et al., and Navarro et al.
The effects of chair intervention on lower back pain, discomfort and trunk muscle activation in office workers: a systematic review
Published in International Journal of Occupational Safety and Ergonomics, 2022
Sirinant Channak, Thaniya Klinsophon, Prawit Janwantanakul
All included studies failed to blind both care providers who administered the intervention and outcome assessors. Only one study was able to successfully blind participants. Blinding of all participants, care providers and outcome assessors is important for the internal validity of the study [43]. One of the most effective research tools to control for a placebo effect or Hawthorne effect is blinding [44]. Participants in the control group would have had no expectations, but the intervention group was prone to expectations. Blinding of care providers who administered the intervention or outcome assessors is also important to guarantee that the apparent effect of treatment is not due to the provider’s or assessor’s enthusiasm or lack of enthusiasm for the intervention or control condition [45]. One strategy that could be conducted to minimize the expectation bias of participants and outcome assessors is to set a trial in which two chair types are compared and ensure that the chairs are equally credible and acceptable to participants and outcome assessors, and that both participants and outcome assessors have limited experience or expectations regarding either chair type.