The Kemahiran Proses Sains Tahap Empat: Satu instrumen untuk Pelajar Tingkatan Empat Sekolah Menengah

Kajian ini bertujuan menentukan kesahan dan kebolehpercayaan instrumen Ujian Kemahiran Proses Sains Tahap Empat (UKPST4) menggunakan Model Pengukuran Rasch. UKPST4 dibangunkan untuk mengukur penguasaan Kemahiran Proses Sains (KPS) Tahap Empat pelajar Tingkatan Empat di sekolah menengah. UKPS4 terdiri daripada 26 item jenis struktur yang mengandungi lima pecahan konstruk KPS iaitu: mengenal pasti pemboleh ubah dimanipulasikan, pemboleh ubah bergerak balas, dan pemboleh ubah dimalarkan, membina hipotesis, membuat pemerhatian, membuat inferens, dan mendefinisikan secara operasi. Sampel kajian terdiri daripada 60 orang pelajar Tingkatan Empat dari sebuah sekolah bandar di daerah Lawas, Sarawak. Hasil analisis kesahan mendapati polariti item melalui nilai PTMEA-Corr menunjukkan bahawa kesemua 26 item berada >0.00 (+). Melalui analisis kesesuaian item, semua item dikekalkan kerana memenuhi syarat dalam salah satu julat outfit MNSQ, Outfit ZSTD dan PTMEA-Corr. Dalam analisis komponen utama (PCA), nilai Raw Variance Explained by Measures 40.6% dan nilai Unexplained variance dalam kontras pertama hingga kelima di bawah 15% menunjukkan bahawa instrumen mempunyai keekadimensian yang kuat dan mempunyai kesahan konstruk yang tinggi. Kebolehpercayaan Cronbach Alpha (KR-20) menunjukkan nilai 0.77 (baik), kebolehpercayaan item 0.76 (baik) dan responden 0.73 (mencukupi) dengan nilai pengasingan item 4.78 (baik) dan responden 1.66 (boleh diterima). Kesimpulannya, UKPST4 mempunyai kesahan dan kebolehpercayaan yang baik dalam mengukur penguasaan KPS Tahap Empat pelajar Tingkatan Empat di sekolah menengah.

Quality control strategies for brain MRI segmentation and parcellation: practical approaches and recommendations - insights from The Maastricht Study

ABSTRACTBackgroundQuality control of brain segmentation is a fundamental step to ensure data quality. Manual quality control is the current gold standard, despite unfeasible in large neuroimaging samples. Several options for automated quality control have been proposed, providing potential time efficient and reproducible alternatives. However, those have never been compared side to side, which prevents to reach consensus in the appropriate QC strategy to use. This study aims to elucidate the changes manual editing of brain segmentations produce in morphological estimates, and to analyze and compare the effects of different quality control strategies in the reduction of the measurement error.MethodsWe used structural MR images from 259 participants of The Maastricht Study. Morphological estimates were automatically extracted using FreeSurfer 6.0. A subsample of the brain segmentations with inaccuracies was manually edited, and morphological estimates were compared before and after editing. In parallel, 11 quality control strategies were applied to the full sample. Those included: a manual strategy, manual-QC, in which images were visually inspected and manually edited; five automated strategies where outliers were excluded based on the tools MRIQC and Qoala-T, and the metrics morphological global measures, Euler numbers and Contrast-to-Noise ratio; and five semi-automated strategies, were the outliers detected through the mentioned tools and metrics were not excluded, but visually inspected and manually edited. We used a regression of morphological brain measures against age as a test case to compare the changes in relative unexplained variance that each quality control strategy produces, using the reduction of relative unexplained variance as a measure of increase in quality.ResultsManually editing brain surfaces produced changes particularly high in subcortical brain volumes and moderate in cortical surface area, thickness and hippocampal volumes. The exclusion of outliers based on Euler numbers yielded a larger reduction of relative unexplained variance for measurements of cortical area, subcortical volumes and hippocampal subfields, while manual editing of brain segmentations performed best for cortical thickness. MRIQC produced a lower, but consistent for all types of measures, reduction in relative unexplained variance. Unexpectedly, the exclusion of outliers based on global morphological measures produced an increase of relative unexplained variance, potentially removing more morphological information than noise from the sample.ConclusionOverall, the automatic exclusion of outliers based on Euler numbers or MRIQC are reliable and time efficient quality control strategies that can be applied in large neuroimaging cohorts.

Determinants of Medical Practice Variation Among Primary Care Physicians: Protocol for a Three Phase Study

Background One of the greatest challenges of modern health systems is the choice and use of resources needed to diagnose and treat patients. Medical practice variation (MPV) is a broad term which entails the differences between health care providers inclusive of both the overuse and underuse. In this paper, we describe a 3-phase research protocol examining MPV in primary care. Objective We aim to identify the potential targets for behavioral modification interventions to reduce the variation in practice patterns and thus improve health care, decrease costs, and prevent disparities in care. Methods The first phase will delineate the variation in primary care practice over a wide range of services and long follow-up period (2003-2017), the second will examine the 3 determinants of variation (ie, patient, physician, and clinic characteristics), and attempt to derive the unexplained variance. In the third phase, we will assess a novel component that might contribute to the previously unexplained variance - the physicians’ personal behavioral characteristics (such as risk aversion, fear of malpractice, stress from uncertainty, empathy, and burnout). Results This work was supported by the research grant from Israel National Institute for Health Policy Research (Grant No. 2014/134). Soroka University Medical Center Institutional Ethics Committee has approved the updated version of the study protocol (SOR-14-0063) in February 2019. All relevant data for phases 1 and 2, including patient, physician, and clinic, were collected from the Clalit Health Services data set in 2019 and are currently being analyzed. The evaluation of the individual physician characteristics (eg, risk aversion) by the face-to-face questionnaires was started on 2018 and remains in progress. We intend to publish the results during 2020-2021. Conclusions Based on the results of our study, we aim to propose a list of potential targets for focused behavioral intervention. Identifying new targets for such an intervention can potentially lead to a decrease in the unwarranted variation in the medical practice. We suggest that such an intervention will result in optimization of the health system, improvement of health outcomes, reduction of disparities in care and savings in cost. International Registered Report Identifier (IRRID) DERR1-10.2196/18673

Analisis Rasch bagi Ujian Pemikiran Sains Keusahawanan dalam Pendidikan STEM Sekolah Rendah

Instrumen Ujian Pemikiran Sains Keusahawanan (UPSK) telah dibina bertujuan mengukur pemikiran sains keusahawanan dalam Pendidikan STEM sekolah rendah. Kajian ini bertujuan mennentukan kualiti instrumen UPSK melalui kesahan dan kebolehpercayaan instrumen UPSK melalui Model Pengukuran Rasch. UPSK adalah rangkuman soalan terbuka yang terdiri daripada sepuluh item dengan lima pecahan konstruk iaitu: pemerhatian, idea baharu, inovasi, kreativiti dan nilai. Sampel terdiri daripada 166 orang pelajar yang berusia 10 hingga 11 tahun dari sekolah-sekolah bandar di daerah Tawau, Sabah. Hasil analisis kesahan mendapati polariti item melalui nilai PTMEA-Corr menunjukkan bahawa kesemua 10 item berada >0.00 (+). Melalui analisis kesesuaian item, semua item masih dikekalkan kerana memenuhi syarat dalam salah satu julat outfit MNSQ, Outfit ZSTD dan PTMEA-Corr. Dalam analisis komponen utama (PCA), nilai Raw Variance Explained by Measures 66.8% (cemerlang) dan nilai Unexplained variance dalam kontras pertama di bawah 15% menunjukkan bahawa instrumen mempunyai keekadimensian yang kuat dan mempunyai kesahan konstruk yang tinggi. Kebolehpercayaan Cronbach Alpha (KR-20) menunjukkan nilai 0.91 (sangat tinggi), kebolehpercayaan item 0.98 (cemerlang) dan responden 0.89 (baik) dengan nilai pengasingan item 7.97 dan responden 2.83. Kesimpulannya, UPSK mempunyai kesahan yang baik dan kebolehpercayaan yang tinggi dalam mengukur pemikiran sains keusahawanan dalam kalangan pelajar tahun lima di sekolah rendah di Sabah.

Determinants of Medical Practice Variation Among Primary Care Physicians: Protocol for a Three Phase Study (Preprint)

BACKGROUND One of the greatest challenges of modern health systems is the choice and use of resources needed to diagnose and treat patients. Medical practice variation (MPV) is a broad term which entails the differences between health care providers inclusive of both the overuse and underuse. In this paper, we describe a 3-phase research protocol examining MPV in primary care. OBJECTIVE We aim to identify the potential targets for behavioral modification interventions to reduce the variation in practice patterns and thus improve health care, decrease costs, and prevent disparities in care. METHODS The first phase will delineate the variation in primary care practice over a wide range of services and long follow-up period (2003-2017), the second will examine the 3 determinants of variation (ie, patient, physician, and clinic characteristics), and attempt to derive the unexplained variance. In the third phase, we will assess a novel component that might contribute to the previously unexplained variance - the physicians’ personal behavioral characteristics (such as risk aversion, fear of malpractice, stress from uncertainty, empathy, and burnout). RESULTS This work was supported by the research grant from Israel National Institute for Health Policy Research (Grant No. 2014/134). Soroka University Medical Center Institutional Ethics Committee has approved the updated version of the study protocol (SOR-14-0063) in February 2019. All relevant data for phases 1 and 2, including patient, physician, and clinic, were collected from the Clalit Health Services data set in 2019 and are currently being analyzed. The evaluation of the individual physician characteristics (eg, risk aversion) by the face-to-face questionnaires was started on 2018 and remains in progress. We intend to publish the results during 2020-2021. CONCLUSIONS Based on the results of our study, we aim to propose a list of potential targets for focused behavioral intervention. Identifying new targets for such an intervention can potentially lead to a decrease in the unwarranted variation in the medical practice. We suggest that such an intervention will result in optimization of the health system, improvement of health outcomes, reduction of disparities in care and savings in cost. INTERNATIONAL REGISTERED REPORT DERR1-10.2196/18673

Confound modelling in UK Biobank brain imaging

Dealing with confounds is an essential step in large cohort studies to address problems such as unexplained variance and spurious correlations. UK Biobank is a powerful resource for studying associations between imaging and nonimaging measures such as lifestyle factors and health outcomes, in part because of the large subject numbers. However, the resulting high statistical power also raises the sensitivity to confound effects, which therefore have to be carefully considered. In this work we describe a set of possible confounds (including non-linear effects and interactions) that researchers may wish to consider for their studies using such data. We include descriptions of how we can estimate the confounds, and study the extent to which each of these confounds affects the data, and the spurious correlations that may arise if they are not controlled. Finally, we discuss several issues that future studies should consider when dealing with confounds.

Polarized perceptions, polarized preferences? Understanding the relationship between inequality and preferences for redistribution

When studying the relationship between inequality and preferences for redistribution, it is often assumed – either implicitly or explicitly – that individuals are informed about actual levels of inequality. Newer research, however, challenges this assumption and shows that perceived inequality differs from actual inequality. Empirically, these inequality perceptions are rather good predictors for preferences for redistribution. This article argues that individuals answer the standard question for measuring preferences for redistribution based on their inequality perceptions. I conduct a simple regression analysis based on two waves of the ISSP (1999 and 2009) and show that (1) inequality perceptions are systematically linked to socio-economic variables as well as to ideological beliefs rather than to actual inequality. Then, I disaggregate the variance in inequality perceptions to a part which is explainable by socio-economic and ideological determinants (the common control variables for explaining preferences for redistribution) and an unexplained part. I show that (2) the explained as well as the unexplained variance part is associated with preferences for redistribution. I argue that this finding makes considering inequality perceptions practically relevant since standard control variables do not fully account for variation in perceived inequality.