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. 2021 Sep 7;10(18):4047. doi: 10.3390/jcm10184047

Table A3.

Formulae used to calculate the G and Φ generalizability coefficients in Table 3, derived from references [20,21]. Abbreviations: A, aid or calibration level; J, temporomandibular joint; P, patient; R, reader; S, specialty (binary, radiologist or non-radiologist clinician); colon (:), nested relation, (e.g., J:P means joint is nested within the patient variable); cross (x), crossed relation (e.g., RxA means each Reader provides data at all levels of the aid variable).

Coefficient Meaning Formula
J:P × R × A Design—Pooling Across Use or Disuse of Aid, Separately for Radiologist and Non-Radiologist Readers
Between readers of the same calibration (R random, P and A fixed) G(R)=J:P+AJ:PJ:P+AJ:P+R+RJ:P+ARJ:P
Same reader with vs. without aid (A random, P and R fixed) G(A)=J:P+RJ:PJ:P+RJ:P+A+AJ:P+ARJ:P
Between readers with different calibration (A and R random, P fixed) G(R,A)=J:PJ:P+A+R+AR+AJ:P+RJ:P+ARJ:P
Between readers with different calibration, averaging 2 readings per reader (A and R random, P fixed, A/2) G(R,A)=J:PJ:P+A2+R+AR2+AJ:P2+RJ:P+ARJ:P2
Between readers with different calibration, averaging 2 readers at a time (A and R random, P fixed, R/2) G(R,A)=J:PJ:P+A+R2+AR2+AJ:P+RJ:P2+ARJ:P2
Between readers of the same calibration, averaging two readers at a time (R random, P and A fixed, R/2) G(R)=J:P+AJ:PJ:P+AJ:P+R2+RJ:P2+ARJ:P2
Right-left joint agreement when scored by different readers with different calibration (J, A and R random) Φ(J,R,A)=PP+J:P+R+A+PA+PR+AR+PAR+AJ:P+RJ:P+ARJ:P
Right-left joint agreement when scored by the same reader with the same calibration (J random, A and R fixed) G(J)=P+PA+PR+PARP+PA+PR+PAR+J:P+AJ:P+RJ:P+ARJ:P
J:P × R:S Design—Pooling Across Radiologist and Non-Radiologist Readers, Separately for Each Aid
Between radiologists and non-radiologists (R and S random, P fixed) G(R,S)=J:PJ:P+R:S+S+J:PS+JR:PS
Between readers of the same specialty (R random, S and P fixed) G(R)=J:P+J:PSJ:P+J:PS+R:S+JR:PS
Right-left joint agreement when scored by radiologist and non-radiologist (J, S and R random) Φ(J,R,S)=PP+J:P+R:S+S+PS+PR:S+J:PS+JR:PS
Right-left joint agreement when scored by the same reader (J random, R and S fixed) G(J)=P+PS+PR:SP+PS+PR:S+J:P+J:PS+JR:PS