Statistical problems caused by missing data resulting from neodymium:YAG laser capsulotomies in long-term posterior capsule opacification studies

摘要: Purpose To describe a way to eliminate the problem caused by missing data due neodymium:YAG (Nd:YAG) laser capsulotomies before statistical analysis, which leads incomplete in long-term studies of posterior capsule opacification (PCO). Setting Medical University Vienna, Austria. Methods demonstrate problem, an existing study comparing PCO development eyes with round-edged and sharp-edged intraocular lenses (IOLs) was analyzed. In study, several Nd:YAG led dropouts IOL group. solve resulting value values were replaced estimated various scenarios; that is, different assumptions made how would have developed without capsulotomy. Standard analyses included rather than excluding cases then performed. Results The analysis all (including scores) showed highly significant difference between group Sensitivity confirmed 2 groups remained up implausible chosen for scores, thus proving correctness analysis. Conclusions This it is possible perform cases. approach recommended as increases power. Excluding may lead biased or wrong conclusions.