Turkiye Klinikleri Journal of Biostatistics

.: ORIGINAL RESEARCH
Investigation of the Factors Affecting the Consistency Assumption of Network Meta-Analysis: A Simulation Study
Ağ Meta Analizinde Tutarlılık Varsayımını Etkileyen Faktörlerin Araştırılması: Bir Benzetim Çalışması
Didem DERİCİ YILDIRIMa, Sahure ÖZERTÜRKa, Damla Hazal SUCUa
aDepartment of Biostatistics and Medical Informatics, Mersin University Faculty of Medicine, Mersin, Türkiye
Turkiye Klinikleri J Biostat. 2022;14(2):110-7
doi: 10.5336/biostatic.2022-90130
Article Language: EN
Full Text
ABSTRACT
 Objective: This study aimed to examine the factors affecting consistency assumption with simulated data for network meta-analyses. Network pattern, number of studies per comparison, individual study sample sizes, and probabilities of the event were investigated that may affect the consistency assumption. Material and Methods: Data were produced with R 4.1.0 for the combination of different sample sizes (N: 100, 150, 200), the different success probability of three treatments (p1, p2, p3 changes in interval 0.01-0.90), and the number of study per comparison (M=5, M=10, M=20, M=30). Then the mean and standard error of ratios of odds ratios (ROR) were calculated and this process was repeated 1,000 times. Results: We found that the success probability of treatments and the number of studies in the network affected the inconsistency assumption more than the study sample size for N=100 and N=150. Also, the results indicated that in sample size 200, the study sample size affected the ROR values in addition to the other factors. Conclusion: Network meta-analysis is wide-spreading in recent years. Therefore, it is important to obtain reliable results with the providing assumptions. Especially, consistency assumption must be considered and the researchers may realize the affecting factors of the consistency assumption with this study.

Keywords: Network meta-analysis; consistency assumption; indirect comparison
ÖZET
 Amaç: Bu çalışma, ağ meta analizi için simüle edilmiş verilerle, tutarlılık varsayımını etkileyen faktörleri incelemeyi amaçlamıştır. Tutarlılık varsayımını etkileyebilecek; ağ modeli, karşılaştırma başına çalışma sayısı, bireysel çalışma örneklem büyüklükleri ve tedavilerin başarı olasılıkları dikkate alınmıştır. Gereç ve Yöntemler: Veriler farklı örneklem büyüklüklerinin kombinasyonu (N: 100, 150, 200), 3 tedavinin farklı başarı olasılığı (0,01-0,90 aralığında değişen p1, p2, p3) ve karşılaştırma başına çalışma sayısı (M=5, M=10, M=20, M=30) için R 4.1.0 yazılımı ile üretilerek, sonuçlar elde edilmiştir. Daha sonra göreceli olasılıklar oranı [ratios of odds ratios (ROR)] değerleri için ortalama ve standart hata hesaplanmış ve bu işlem 1.000 kez tekrar edilmiştir. Bulgular: N=100 ve N=150 için tedavilerin başarı olasılığının ve ağdaki çalışma sayısının tutarsızlık varsayımını, çalışma örneklem büyüklüğünden daha fazla etkilediği tespit edilmiştir. Ayrıca sonuçlar, örneklem büyüklüğü 200 olduğunda, diğer faktörlere ek olarak, örneklem büyüklüğünün de ROR değerlerini etkilediğini göstermiştir. Sonuç: Ağ meta analizi son yıllarda gittikçe yaygınlaşmaktadır. Bu nedenle sağlanan varsayımlarla güvenilir sonuçlar elde etmek önemlidir. Özellikle tutarlılık varsayımının incelenmesi gerekir ve araştırmacılar bu çalışma ile tutarlılık varsayımını etkileyen faktörleri dikkate alabilirler.

Anahtar Kelimeler: Ağ meta analizi; tutarlılık varsayımı; dolaylı karşılaştırma
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