Hair Fall Count 60-second: Clinic-Based Modified Count Versus Home-Based Count

Background: Female diffuse alopecia is a common dermatologic problem. Consequently, a simple, quick, and quantitative assessment is required to aid in diagnosis. A clinic-based modified hair fall count in 60 seconds is proposed as a new, simple, and quick method for evaluating hair loss. Objectives: To assess bias and limit of agreement between the new Clinic-based modified hair fall count in 60 seconds (CBMHFC 60-S) and conventional home-based hair fall count in 60 seconds (HBHFC 60-S) determining hair fall in women with diffuse hair loss. Materials and Methods: Seventy-five women with diffuse alopecia recruited from Al-Salam Teaching Hospital, Mosul, Iraq underwent assessment of hair fall count by using two instruments, new single reading (CBMHFC 60-S) and conventional three reading (HBHFC 60-S). A multistage statistical analysis of validity tests was used to assess the performance of CBMHFC 60-S in comparison to HBHFC 60-S. These included the estimation of the difference between both methods; correlation and prediction; and lastly estimating accuracy (amount of bias and limits of agreement) using Bland Altman blot. A P-value < 0.05 was considered a statistically significant difference. Results: A non-statistically significant difference (P-value = 0.06) in average hair fall count was estimated by CBMHFC 60-S and HBFHFC 60-S (15.81 ± 7.16 vs 18.18 ± 8.56). A very highly significant linear relationship between both tests (r = 0.434, P-value <0.0001). A regression analysis yields the following prediction equation [CBMHFC 60-S = 9.21 + 0.36* (HBHFC 60-S)]. Bland-Altman blot revealed a high accuracy of the CBHFC 60-S. The count was less than HBHFC 60-S count by an average of 2.38 hairs. The 95% CI of CBMHFC 60-s in comparison to HBHFC 60-S will fall between -18.95 and 14.19. Conclusion: The new single reading CBMHFC-60S estimation of hair fall count was a valid test reflected by its strong association with an average of three readings of conventional HBHFC-60 and high concordance (low bias and high precision).