Table 5.

IRR and 95% CI for quasi-Poisson regression.

	N	IRR	95% CI	P value
By injured location
Upper arm	1783	1.00	–
Forearm	9528	4.33	4.02–4.66	<.001
Hand and Wrist	15,197	6.78	6.31–7.29	<.001
Finger	30,678	33.91	31.47–36.54	<.001
By season
Autumn	14,527	1.00	–
Spring	13,722	0.95	0.92–0.98	<.001
Summer	17,005	1.16	1.13–1.20	<.001
Winter	11,932	0.83	0.80–0.86	<.001
By gender
Female	17,623	1.00	–
Male	39,563	2.14	2.12–2.16	<.001

Patients whose specific injury area could not be identified were excluded in the analysis.

CI = confidence interval, IRR = incidence rate ratio, N = number of patients with peripheral nerve injury, the number of patients.