Sudden loading perturbation to determine the reflex response of different back muscles: a reliability study.

In this study we estimate the reliability of reflex response variables to identify the main sources of variability and to estimate appropriate measurement strategies to obtain more reliable measures. Back muscle surface electromyography (EMG) was recorded in healthy males during anteriorly-directed sudden loading perturbations applied to the trunk. Measures of EMG reflex latency and amplitude were obtained. The generalizability theory was used as a framework to estimate the magnitude of the different variance components and the reliability of the measures corresponding to various simulations of different measurement strategies. Reliability of the different variables was poor to moderate (intraclass correlation coefficient range 0-0.62). Averaging scores across homologous muscles and several trials were strategies to achieve more acceptable reliability. The reflex response of back muscles is inherently variable, and a large measurement effort is necessary to obtain reliable and, consequently, valid and responsive estimations of this neuromuscular function.

The Work Disability Prevention CIHR Strategic Training Program: program performance after 5 years of implementation.

INTRODUCTION: The Work Disability Prevention (WDP) Canadian Institutes of Health Research (CIHR) Strategic Training Program was developed in 2001 and is a unique program in the world. The main objective of this program is to help future researchers develop transdisciplinary knowledge, skills and attitudes regarding WDP. The purpose of this paper is to present a descriptive portrait of the program's performance over the past 5 years, as well as the trainees' and alumni's perspectives on the WDP CIHR Training Program. METHODS: Data on the program's performance were collected from documents in the program records. The trainees' opinions on the WDP training program were obtained through focus groups and telephone interviews. The data collected were compiled and divided into themes to summarize the qualitative findings pertaining to each question. RESULTS: From 2003 to 2007, five successive summer sessions have been offered, involving 44 high-caliber applicants from nine countries, 34 mentors and collaborators, 29 guest speakers and 15 stakeholders. Overall, trainees appreciated the networking, the opportunity to interact with people from different disciplines and countries, the openness, and the international perspective and uniqueness of the program. The least appreciated aspects concerned mainly the e-learning course, evaluations and information on optional courses. The coordination and logistics were judged appropriate and several topics were suggested to improve the program quality. CONCLUSION: In general, the program implementation went well, with good participation from mentors, speakers and stakeholders; the program was appreciated by the trainees and alumni. This paper underscores the importance of the international perspective, the transdisciplinarity and the scientific networking established through the program.

Reliability of centre of pressure summary measures of postural steadiness in healthy young adults.

This study aimed to (1) estimate the reliability of 36 centre of pressure (COP) summary measures in healthy participants and (2) identify the main sources of variability in order to estimate the most appropriate measurement strategies to improve reliability. Twelve healthy males performed, on two separate days, eight 1-min trials of quiet standing on a force platform in two conditions [eyes open (EO) and eyes closed (EC)]. The generalizability theory was used as a framework to estimate the magnitude of the different variance components (Subject, Trial, Day and all interactions) and the reliability of the measures corresponding to various simulations of measurement strategies. Reliability of the COP summary measures was poor to moderate. Intra-class correlation coefficients were generally higher with EO (mean: 0.46, range: 0.03-0.76) than with EC (mean: 0.41, range 0.02-0.72) across all summary measures. The majority of the variance was attributed to Subject (2%-76%), Subject x Day (0%-24%) and Subject x Day x Trial (16%-79%) variance components depending on the summary measure and condition. The reliability could be improved more efficiently by averaging measurements between-days than by increasing the number of trials during 1 day. For the majority of the summary measures, acceptable reliability can be achieved when at least seven or more trials are averaged during the same testing day.