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Objectives To develop a per-patient volume correction for maximum flow rate using multiple home uroflowmetry, and to carry out a pilot study to determine the most prognostically useful volume at which to evaluate this measurement and estimate its relationship with outcome from disobstructive bladder outlet surgery. Methods A total of 30 men carried out home uroflowmetry using a portable device and completed symptom scores before surgery. This was repeated at least 4 months after surgery. For each man's presurgery flow data, voided volume was plotted against maximum flow rate, and a line of best fit with logarithmic form calculated. This allowed maximum flow rate to be corrected for any volume. Percentage reduction in symptom score and increase in mean maximum flow rate were correlated with volume-corrected maximum flow rates. Results Corrected maximum flow rate at all volumes showed the expected negative correlation with both outcome measures. A statistically significant correlation occurred for volumes >190 mL, with the best performance at volumes >300 mL. Conclusions We have devised a novel method allowing estimation of maximum flow rate at any volume, which is a step forward for non-invasive diagnostics. We found this volume-corrected maximum flow rate to correlate significantly with treatment outcome at sufficiently high volumes.

Aims Uroflowmetry is a key clinical assessment for men with LUTS. Home uroflowmetry is a convenient way to obtain multiple flow readings and has the potential to combat problems inherent to clinic-based measurements. We reviewed current evidence regarding the technology and value of multiple and home uroflowmetry. Methods We searched PubMed and Embase from January 1988 to February 2011 using a predetermined strategy. Reference lists from retrieved articles were scanned and additional papers screened for relevance. Proceedings of the annual meetings of the International Continence Society since 2008 were also searched. Relevant guidelines were obtained from the UK NHS Evidence repository. Results Eight studies described five simple, low-cost instruments giving multiple representative estimates of Qmax but not a complete flow curve. A further eight studies described home use of four sophisticated, electronic flowmeters similar to clinic-based equipment. The above methods were assessed against ICS recommendations for uroflowmetry and the results of several studies investigating variability of flow parameters such as Qmax were presented. Conclusions Our findings illustrate the gulf between low-cost methods of obtaining average or peak flow measurements and precise, expensive devices with the capabilities of clinic flowmeters. Further studies are required to confirm the statistical benefit of averaging multiple values of Qmax and to investigate the diagnostic and predictive value of flow variables other than Qmax that can be derived from multiple recordings. Neurourol. Urodynam. 31:7–12, 2012. © 2011 Wiley Periodicals, Inc.