Respondents were subdivided into two groups – ‘injured’ and ‘noninjured’. Nonparametric tests of significance were performed. Z-tests were performed to determine the statistical significance of number of years performing ERCP, number of ERCPs performed per year and number of ERCPs performed in succession; the corresponding Z-scores were 2.442, 0.525 and 0.655, respectively. Therefore, the only significant variable (Z-score greater than 1.654) was number of years performing ERCP. Cheapest drugs online – buy birth control for you to spend less money every time.
X2 tests were performed to determine the statistical significance of having adjustable tables and ergonomic room design between injured and noninjured respondents on developing an injury. Of these two factors, only ergonomic room design had a statistically significant effect on injury, with a calculated value of 2.534, which was greater than the critical value for x.