a significant trendP =0.002
There was a significant trend for duration of use ( P trend =0.004) with an OR of 0.66 (95% CI 0.51–0.86, P =0.002) for more than 24 months of use.
There was a significant trend for duration of use ( P trend =0.004) with an OR of 0.66 (95% CI 0.51–0.86, P =0.002) for more than 24 months of use.