Systematic review with meta-analysis: defecography should be a first-line diagnostic modality in patients with refractory constipation

Because of a lack of a control group, a case-series study is considered one of the weaker study designs from which to obtain evidence on treatment effectiveness. Under certain circumstances, however, this is the only available evidence to inform health-care decisions. This study's intent was to develop and validate a quality appraisal checklist specifically for case-series studies.