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Journals / Psikoloji Araştırmaları / 2026 / Cilt: 3 Sayı: 2

Evaluating Individual Change in Psychotherapies: Single-Case Experimental Studies

Psikoterapilerde Bireysel Değişimi Değerlendirmek: Tek Olgulu Deneysel Çalışmalar

Ahmet Nalbant
Havvanur Uysal Akdemir
Rumeysa Yıldız0009-0005-0459-2706
Edanur Gürbüz Taşyildiz0009-0008-7192-8275
Merve Terzioğlu
Fatih Yavuz
Pages
42–62
Publication Date
2026-05-31
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Additionally, its potential applications in psychotherapy research and key considerations are discussed.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:The effectiveness of psychotherapies has been a debated issue for many years, and randomized controlled trials (RCTs) have generally been accepted as the gold standard for evaluating the efficacy of psychotherapy methods.
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Key Findings & Data:SCED is an experimental research method that has been used for a long time to demonstrate the effectiveness of interventions made on the same individual.
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Conclusion & Impact:Additionally, its potential applications in psychotherapy research and key considerations are discussed.
🔬Design:Derleme
📍Scope:Comprehensive Sample
⚙️Variables:psikoterapi · etkililik · randomize kontollü çalışma

Abstract

The effectiveness of psychotherapies has been a debated issue for many years, and randomized controlled trials (RCTs) have generally been accepted as the gold standard for evaluating the efficacy of psychotherapy methods. However, RCTs have faced criticisms for being costly, having generalizability problems, and ignoring individual changes. Single-case experimental design (SCED) offer an effective alternative to observe change in individuals. SCED is an experimental research method that has been used for a long time to demonstrate the effectiveness of interventions made on the same individual. Although SCED is widely used in fields such as special education, its use in psychotherapy effectiveness studies is relatively low, especially in our country. However, interest in this method is gradually increasing. In this article, the general framework and basic principles of SCED, its advantages, study designs, measurement, and analysis methods are examined. Additionally, its potential applications in psychotherapy research and key considerations are discussed.

Özet

Psikoterapilerin etkililiği uzun yıllardır araştırma konusu olmakla birlikte, bu etkililiğin nasıl ve hangi yöntemlerle değerlendirileceği hâlen tartışılmaktadır. Psikoterapi yönteminin etkili olup olmadığını değerlendirmek için randomize kontrollü çalışmalar (RKÇ) altın standart olarak kabul edilmiştir. Ancak RKÇ’ın maliyetli oluşu, genellenebilirlik sorunları ve bireysel değişimleri göz ardı etmesi gibi eleştiriler mevcuttur. Özellikle psikoterapi süreçlerinde değişimin bireyler arasında ve birey içinde farklı biçimlerde ortaya çıkabilmesi, yalnızca grup ortalamalarına dayalı değerlendirmelerin klinik uygulamalar açısından yetersiz kalmasına yol açmaktadır Bu bağlamda, tek olgulu deneysel çalışmalar (TODÇ), bireylerdeki değişimi ayrıntılı biçimde incelemeye olanak tanıyan güçlü bir alternatif araştırma yöntemi sunmaktadır. Tek olgulu deneysel çalışma, herhangi bir kişiye yapılan bir müdahalenin etkililiğinin yine aynı birey üzerinden gösterilmesi için uzun zamandır kullanılan deneysel bir araştırma yöntemidir. Bu yöntem özellikle özel eğitim alanında yaygın olarak kullanılmakla birlikte, psikoterapi etkililik araştırmalarında, özellikle Türkiye’de, görece sınırlı düzeyde yer almaktadır. Ancak son yıllarda bireyselleştirilmiş müdahalelere ve süreç temelli yaklaşımlara olan ilginin artmasıyla birlikte TODÇ’lere yönelik ilgi de giderek artmaktadır. Bu derleme çalışmasında, tek olgulu deneysel çalışmaların kuramsal temelleri ve temel ilkeleri ele alınmış; farklı TODÇ tasarımları, ölçüm stratejileri, analiz yöntemleri ayrıntılı biçimde incelenmiştir. Ayrıca psikoterapi araştırmalarında TODÇ kullanımına ilişkin metodolojik gereklilikler ve dikkat edilmesi gereken noktalar tartışılmıştır. Bu makalenin, psikoterapi alanında bireysel değişimi daha hassas biçimde değerlendirmeye yönelik araştırmalara katkı sağlaması amaçlanmaktadır.

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Cite This Article

Nalbant, A., Akdemir, H. U., Yıldız, R., Taşyildiz, E. G., Terzioğlu, M., Yavuz, F. (2026). Evaluating Individual Change in Psychotherapies: Single-Case Experimental Studies. Psikoloji Araştırmaları, Cilt: 3 Sayı: 2, 42–62. https://ajindex.com/articles/1646189

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