Table 2. Crude and age-standardized 5-year incidence rates and rate ratio of HAM/TSP in Martinique between 1986 and 2010.

Study Periods	Estimated Population at Risk	Events, n	Crude 5-year Incidence Rate (95%CI)	1986–1990 age-standardized 5-year incidence rates (95%CI)	Standardized Incidence Rate Ratio (95%CI)
1986–1990	359,579	36	10.01 (6.78–13.28)	10.01 (6.78–13.28)	1
1991–1995	368,735	48	13.02 (9.34–16.70)	11.93 (8.61–15.25)	1.19 (0.87–1.55)
1996–2000	381,325	44	11.54 (8.13–14.95)	10.37 (7.28–13.47)	1.04 (0.91–1.13)
2001–2005	397,727	17	4.27 (2.24–6.28)	3.13 (1.64–4.62)	0.31 (0.17–0.51)
2006–2010	394,171	8	2.03 (0.62–3.43)	1.34 (0.41–2.27)	0.13 (0.09–0.18)

CI indicates Confidence Interval

The 1986-1990-study period was used as reference for the standardized incidence rate ratio calculation.

According to simple Poisson regression model, P for trend of age-standardized 5-year incidence rates over the study periods was calculated as <0.01.