Cluster randomized trials of individual-level interventions were at high risk of bias.
J Clin Epidemiol
; 138: 49-59, 2021 10.
Article
en En
| MEDLINE
| ID: mdl-34197941
ABSTRACT
OBJECTIVES:
To describe the prevalence of risks of bias in cluster-randomized trials of individual-level interventions, according to the Cochrane Risk of Bias tool. STUDY DESIGN ANDSETTING:
Review undertaken in duplicate of a random sample of 40 primary reports of cluster-randomized trials of individual-level interventions.RESULTS:
The most common reported reasons for adopting cluster randomization were the need to avoid contamination (17, 42.5%) and practical considerations (14, 35%). Of the 40 trials all but one was assessed as being at risk of bias. A majority (27, 67.5%) were assessed as at risk due to the timing of identification and recruitment of participants; many (21, 52.5%) due to an apparent lack of adequate allocation concealment; and many due to selectively reported results (22, 55%), arising from a mixture of reasons including lack of documentation of primary outcome. Other risks mostly occurred infrequently.CONCLUSION:
Many cluster-randomized trials evaluating individual-level interventions appear to be at risk of bias, mostly due to identification and recruitment biases. We recommend that investigators carefully consider the need for cluster randomization; follow recommended procedures to mitigate risks of identification and recruitment bias; and adhere to good reporting practices including clear documentation of primary outcome and allocation concealment methods.Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Proyectos de Investigación
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Ensayos Clínicos Controlados Aleatorios como Asunto
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Sesgo de Publicación
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Investigación Biomédica
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Informe de Investigación
Tipo de estudio:
Clinical_trials
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Etiology_studies
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Guideline
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Prognostic_studies
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Risk_factors_studies
Límite:
Humans
Idioma:
En
Revista:
J Clin Epidemiol
Asunto de la revista:
EPIDEMIOLOGIA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Reino Unido