Reliability and validity of assessment methods available in primary care for bladder outlet obstruction and benign prostatic obstruction in men with lower urinary tract symptoms

Objectives: To systematically review the literature regarding the reliability and validity of assessment methods available in primary care for bladder outlet obstruction or benign prostatic obstruction in men with lower urinary tract symptoms (LUTS). Design: Systematic review with best evidence synthesis. Setting: Primary care. Participants: Men with LUTS due to bladder outlet obstruction or benign prostatic obstruction. Review methods: PubMed, Ebsco/CINAHL and Embase databases were searched for studies on the validity and reliability of assessment methods for bladder outlet obstruction and benign prostatic obstruction in primary care. Methodological quality was assessed with the COSMIN checklist. Studies with poor methodology were excluded from the best evidence synthesis. Results: Of the 5644 studies identified, 61 were scored with the COSMIN checklist, 37 studies were included in the best evidence synthesis, 18 evaluated bladder outlet obstruction and 17 benign prostatic obstruction, 2 evaluated both. Overall, reliability was poorly evaluated. Transrectal and transabdominal ultrasound showed moderate to good validity to evaluate bladder outlet obstruction. Measured prostate volume with these ultrasound methods, to identify benign prostatic obstruction, showed moderate to good accuracy, supported by a moderate to high level of evidence. Uroflowmetry for bladder outlet obstruction showed poor to moderate diagnostic accuracy, depending on used cut-off values. Questionnaires were supported by high-quality evidence, although correlations and diagnostic accuracy were poor to moderate compared with criterion tests. Other methods were supported by low level evidence. Conclusion: Clinicians in primary care can incorporate transabdominal and transrectal ultrasound or uroflowmetry in the evaluation of men with LUTS but should not solely rely on these methods as the diagnostic accuracy is insufficient and reliability remains insufficiently researched. Low-to-moderate levels of evidence for most assessment methods were due to methodological shortcomings and inconsistency in the studies. This highlights the need for better study designs in this domain.