Emine Arzu KANIK, BAHAR TAŞDELEN, SEMRA ERDOĞAN

Klinik denemelerde randomizasyon

Klinik denemelerde randomizasyonun amacı, hastaların deneme gruplarına tamamen şansa bağlı olarak atanmasını sağlamak ve “seçim yanlılığını” önlemektir. Bireyler, randomizasyon yöntemleri kullanılarak, çalışmaya katılma kriterleri bakımından birbirine benzer (homojen) olacak şekilde deneme gruplarına dengeli olarak atanabilirler. Ancak küçük örneklemlerde, gruplarda örneklem sayıları dengeli olmayabilir veya gruplardaki bireyler demografik özellikleri ve başlangıç klinik ölçümleri bakımından birbirine tamamen benzer olmayabilir. Bu çalışmada bu kısıtlılıklara çözüm getirebilecek randomizasyon yöntemleri örneklerle açıklanmaya çalışılmıştır.

Randomization in clinical trials

The purpose of randomization in clinical trials is to assign patients into treatment groups randomly and to prevent “selection bias”. By using randomization methods, the patients can be assigned to groups so that they are similar to each other according to their participation criteria (homogenuous). However, in small samples, sampling distributions in groups may not be balanced or the patients may not be completely similar to each other in their demographical characters and their baseline clinical measurements. In this study, randomization methods which have solutions for this kind of limitations have been explained with some examples.

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