The Differences of the Acromiohumeral Interval Between Supine and Upright Radiographs of the Shoulder

Background: Acromiohumeral interval (AHI) is a measurement method to determine the superior migration of the humeral head in patients with rotator cuff tears.Hypothesis/Purpose: The purpose of this study was to compare the AHI measurement in supine shoulder and upright shoulder radiographs, as well as magnetic resonance imaging (MRI), as well as to report the sensitivity, specificity, and accuracy in detecting full thickness rotator cuff tears.Study Design: Diagnostic study.Methods: From July 2020 to May 2021, evaluation of 86 shoulder radiographs in both supine & upright Grashey views compared with the MRI of the affected shoulder. Measurements of the AHI obtained from both radiographs and MRIs was determined by two independent orthopaedic surgeons. The intraclass correlation of the AHI measurement was tested. The difference between the AHI in each view was determined.Result: The 86 shoulders were divided into 3 groups that included; 1) non-full thickness tear (50%), 2) full thickness (FT) tear 3 cm (33.7%), and 3) FT tear > 3 cm (16.3%). The mean difference of AHI noted was significantly lower in the supine radiographs than with the upright (1.34-1.37 mm.). The mean difference of the AHI was significantly lower in the MRI than the upright (1.62-1.87 mm.). AHI obtained from the supine radiographs and MRI had no significant differences. The area under the curve (AUC) of the upright and supine AHI in the diagnosis of the FT tears were at 0.649 and 0.642 accuracy. Upright AHI 7.09 mm. had 27.9% sensitivity and 100% specificity in diagnosing FT tears with 64% accuracy (p<0.001). The upright AHI cut off value of 9.52 mm. had 60.5% sensitivity, 67.4% specificity, and 64% accuracy (p=0.01). The supine AHI 6.56 mm. had 32.6% sensitivity, 100.0% specificity, and 66.3% accuracy (p<0.01). Supine AHI cut off value of 7.42 mm. had 41.9% sensitivity, 86.0% specificity, and 64.0% accuracy (p=0.004). The inter- and intra-rater reliability of AHI measurement in 3 views were of substantial to almost perfect agreement (0.668-0.824).Conclusion: The AHI in supine radiographs were significantly lower than upright shoulder radiographs in all groups as divided by severity of the rotator cuff tear and was comparable with the MRI. For AHI ≤ 7 mm. in upright shoulder radiographs remains as a good diagnostic test of full thickness rotator cuff tears, while this value was not relevant for use as the cut point in the supine radiographs and MRI shoulders.Level of evidence: Level III; Diagnostic studyClinical Relevance: The AHI measurement in supine and upright radiographs are reliable and reproducible. The AHI ≤ 7 mm. in upright shoulder radiographs remains as a good diagnostic test of full thickness rotator cuff tears, while this value was not relevant for use as the cut point in the supine radiographs and MRI shoulders.

MENGGUNAKAN MODEL DINA DALAM PENGEMBANGAN TES DIAGNOSTIK UNTUK MENDETEKSI SALAH KONSEPSI

Penelitian ini bertujuan 1) menemukan cara me-ngembangkan tes diagnostik dengan model DINA, sehingga mampu memberikan informasi salah konsepsi dalam aljabar, 2) mengidentifikasi karakteristik tes diagnostik yang baik yang dikembangkan dengan model DINA. Penelitian pengembangan ini merupakan penelitian empirik, dengan pendekatan deskriptif eksploratori. Pendekatan tersebut digunakan untuk mendeskrip-sikan tahapan pengembangan tes dan mencari karakteristik item. Subjek penelitian adalah siswa kelas VIII SMPN 1 Yogyakarta, SMPN 1 Sanden Bantul dan SMPN 1 Panjatan Kulon Progo. Data dianalisis dengan software CDM, Mplus dan R. Hasil penelitian menunjukan 1) tahapan pengembangan tes meliputi: identifikasi kompetensi dasar dan merumuskan indi-kator, menyusun learning continuum, menyusun hierarki materi, merumuskan atribut, mengonstruk soal, validasi ahli dan uji empirik. Setelah melalui tujuh tahapan, dikembangkan 37 item tes diagnostik, 2) dari 37 item tes diagnostik, 15 item di antaranya harus dihilangkan/dihapus dari paket tes, karena tidak memenuhi uji fit model dan kualitas item tersebut jelek (indeks daya beda kurang dari 0,2).Kata kunci: DINA, latent class, atribut, salah konsepsi, dan aljabar _____________________________________________________________ DINA IN DEVELOPMENT MODEL USING DIAGNOSTIC TESTS FOR DETECTING WRONG CONCEPTIONAbstract This research aims to 1) find out a way to develop the diagnostic test using the DINA model, so that it can give information about misconceptions in algebra, 2) Identify the characteristics of the good diagnostic test developed by using the DINA model. This research and development is an empirical research with the descriptive explanatory used to describe the development stages of the test. The subjects of this research were year VIII students of SMPN 1 Yogyakarta, SMPN 1 Sanden Bantul, and SMPN 1 Panjatan, Kulon Progo. The data were analyzed by using the CDM, Mplus, and R software. The results of the study are as follows 1) The stages of the test development in this research were: identifying basic competence and formulating indicators, constructing the learning continuum, constructing the material hierarchy, formulating the attributes, constructing the problems, conducting validation by expert judgment, and administering an empirical test. Through those seven stages, 37 items of the diagnostic test were developed, 2) Of the 37 items, 15 items must be eliminated/discarded from the test. The items were eliminated because their quality was low and they did not meet the requirements of the model fit test because their discrimination indexes were less than 0.2.Keywords: DINA, latent class, attribute, misconceptions, and algebra

The Concept of Good Classification (Diagnostic) Test

In this chapter, the definition of good diagnostic test and the characterization of good tests are introduced and the concepts of good maximally redundant and good irredundant tests are given. The algorithms for inferring all kinds of good diagnostic tests are described in detail.