Reliability, validity, and minimal detectable change of the push-off test scores in assessing upper extremity weight-bearing ability

Saurabh P Mehta; Hannah R George; Christian A Goering; Danielle R Shafer; Alan Koester; Steven Novotny

doi:10.1016/j.jht.2017.09.008

Reliability, validity, and minimal detectable change of the push-off test scores in assessing upper extremity weight-bearing ability

J Hand Ther. 2019 Jan-Mar;32(1):103-109. doi: 10.1016/j.jht.2017.09.008.

Authors

Saurabh P Mehta¹, Hannah R George², Christian A Goering³, Danielle R Shafer⁴, Alan Koester⁵, Steven Novotny⁵

Affiliations

¹ School of Physical Therapy, Marshall University, Huntington, WV, USA; Department of Orthopedic Surgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA. Electronic address: mehtas@marshall.edu.
² Spectrum Health Hospital, Grand Rapids, MI, USA.
³ Cincinnati VA Medical Center, Cincinnati, OH, USA.
⁴ School of Physical Therapy, Marshall University, Huntington, WV, USA.
⁵ Department of Orthopedic Surgery, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV, USA.

PMID: 29102478
DOI: 10.1016/j.jht.2017.09.008

Abstract

Study design: Clinical measurement study.

Introduction: The push-off test (POT) was recently conceived and found to be reliable and valid for assessing weight bearing through injured wrist or elbow. However, further research with larger sample can lend credence to the preliminary findings supporting the use of the POT.

Purpose of the study: This study examined the interrater reliability, construct validity, and measurement error for the POT in patients with wrist conditions.

Methods: Participants with musculoskeletal (MSK) wrist conditions were recruited. The performance on the POT, grip isometric strength of wrist extensors was assessed. The shortened version of the Disabilities of the Arm, Shoulder and Hand and numeric pain rating scale were completed. The intraclass correlation coefficient assessed interrater reliability of the POT. Pearson correlation coefficients (r) examined the concurrent relationships between the POT and other measures. The standard error of measurement and the minimal detectable change at 90% confidence interval were assessed as measurement error and index of true change for the POT.

Results: A total of 50 participants with different elbow or wrist conditions (age: 48.1 ± 16.6 years) were included in this study. The results of this study strongly supported the interrater reliability (intraclass correlation coefficient: 0.96 and 0.93 for the affected and unaffected sides, respectively) of the POT in patients with wrist MSK conditions. The POT showed convergent relationships with the grip strength on the injured side (r = 0.89) and the wrist extensor strength (r = 0.7). The POT showed smaller standard error of measurement (1.9 kg). The minimal detectable change at 90% confidence interval for the POT was 4.4 kg for the sample.

Conclusions: This study provides additional evidence to support the reliability and validity of the POT. This is the first study that provides the values for the measurement error and true change on the POT scores in patients with wrist MSK conditions. Further research should examine the responsiveness and discriminant validity of the POT in patients with wrist conditions.

Keywords: Concurrent validity; Interrater reliability; Minimal Detectable Change; Push-off test; Upper extremity; Weight bearing.

Publication types

Validation Study

MeSH terms

Elbow Joint / physiopathology
Exercise Test*
Female
Hand Strength / physiology
Humans
Male
Middle Aged
Muscle Strength Dynamometer
Reproducibility of Results
Upper Extremity / physiology*
Weight-Bearing / physiology*
Wrist Joint / physiopathology