[Current use of statistical methods in five core Chinese medical journals]

To determine the frequency of statistical techniques used in Chinese medical journals, types of statistical errors present, and trends over a 10-year period.

We reviewed the statistical methods used in all original articles published in 5 leading journals in 1985 (n = 640) and 1995 (n = 954).

Compared with 1985, significant improvement was seen in 1995. The proportion of papers using statistical tests increased from 40% to 60% (chi 2 = 60.9, P < 0.01), and more sophisticated statistical methods were used. Of those articles using statistics, the proportion using appropriate methods increased from 22% to 46% (chi 2 = 45.3, P < 0.01). In both years, the most commonly used statistical methods were t tests and contingency tables. The most common errors were presentation of P values without specifying the test used, use of multiple t tests instead of ANOVAs, and use of unpaired t tests when paired tests were required.

The use of statistical methods in Chinese medical journals is improving, and by 1995, the frequency of using statistical methods in published articles was similar to that in other journals around the world. However, the lack of or inappropriate sue of statistics remains a serious problem.