Unsupervised Learning for Detection of Cognitive Distortions in Patient Narratives
摘要
This paper introduces an unsupervised machine learning framework for detecting CDs in psychotherapy transcripts. Our novel pipeline integrates semantic embedding using MiniLM-L6-v2, Principal Component Analysis (75 orthogonal directions, PCA \(_{75}\) ), optimized HDBSCAN clustering (silhouette score = 0.098), and KeyBERT-assisted clinical interpretation. Analysis of 6,057 patient narratives reveals three dominant CD profiles: Social Anxiety with (64.9% distorted utterances), Performance Anxiety (100% distorted utterances), and Mixed Symptoms (noise cluster, r = −0.30). Clinical validation by three licensed psychologists evaluating 100 samples per cluster demonstrates strong cluster coherence (Fleiss’ \(\kappa \) = 0.68, indicating “substantial agreement” per Landis and Koch, 1977). The framework provides clinicians with a scalable taxonomy-free tool for cognitive pattern identification, enabling more efficient treatment personalization and progress monitoring.