The pre-publication history for this paper can be accessed here: http://www.biomedcentral.com/1471-2474/14/17/prepub Ideal for measuring cervical rotation, anteroposterior flexion, and lateral flexion of the cervical spine. To find whether the try-angle guides significantly changed the observed angles of the PIP joint, multiple Wilcoxon signed-rank tests with Bonferroni correction were performed for each rater-instrument-position-subposition data set in respect to the baseline joint angles obtained by using the smallest standard angles. Then the standard differences between the angles of the appropriate try-angles (i.e., between the standard angles) were calculated in respect of the smallest standard angles. Next, the lowest significant standard differences were found between the smallest standard angles and the angles of the try-angles, application of which produced significant changes in the observed PIP joint angles (Additional file 6). The lowest significant standard differences were compared with each other and with the corresponding values of the MDC derived from the SEMs of the study parts A. Analysis of reliability of the diagram evaluation The inter-rater and intra-rater reliability of the electrogoniometer is higher than the universal goniometer but challenging to apply in patients' clinical evaluation, hence used more often for research purposes [1]

A pilot exploration employing a healthy subject and 17 raters was performed to elucidate possible technical problems of the study. Boone, D. C., Azen, S. P., Lin, C., Spence, C., Baron, C., & Lee, L. (1978). Reliability of goniometric measurements. Physical Therapy, 58(11), 1355-1360. For the clinician, however, reliability coefficients are less important than measures of absolute reliability like the standard error of measurement (SEM), which (when multiplied by 1.96) indicates how far from the hypothetical true value [ 38, 39, 45] the measurement obtained by a practitioner could be [ 40]. The SEM enables derivation of other measures of absolute reliability including the limits of agreement [ 46] and the minimal detectable change (MDC). The MDC defines the difference that should be obtained between 2 successive measurements on the same subject over time to state that the real change has occurred. In this study the MDC, also referred to as minimal detectable difference [ 38] or repeatability coefficient [ 45, 47], was found by using formula MDC = SEM x 1.96 x √2 [ 4, 40, 45].Crawshaw J, Chambers J: A concise course in advanced level statistics with worked examples. 2001, Cheltenham, UK: Nelson Thornes, 469-470. 4th Flowers KR, LaStayo P: Effect of total end range time on improving passive range of motion. J Hand Ther. 1994, 7: 150-157. 10.1016/S0894-1130(12)80056-1. All the blanks with the recorded angles of the joints were scanned. The scanned diagrams were magnified, and their angles were measured to the nearest degree by the same researcher with ImageJ program. Each diagram was measured at least twice without reference to the previous results. If the results of the two computerized measurements were different, the diagram was remeasured again. If 2 identical measurements were not obtained, mean of the measurements was found and rounded off to the nearest degree. To assess intra-rater and inter-rater reliability of the latter procedure, two invited medical students remeasured 48 randomly chosen scanned diagrams. Computerized evaluation instead of a simple use of a traditional protractor was chosen to equalize varying sizes of the hand drawn diagrams and to avoid errors of hand-done measurements. Independence of observations

Goniometer. (2008, August 30). In Wikipedia, The Free Encyclopedia. Retrieved 11:12, September 14, 2008, from http://en.wikipedia.org/wiki/Goniometer.

Record measurements correctly (both active and passive range of motion should be measured and recorded respectively). [1] The subjects’ task in all study parts was to stabilize their left ring finger joints in postures set up by grasping a funnel or a triangle ruler and by applying appropriate try-angles over the dorsal aspect of the joint (Figure 2a). When evaluating the joints, the raters were required to do their best to align the instrument arms as close as possible to the position of the anatomical axes of the appropriate bones. Dorsal method of placement was used for both instruments. After aligning the arms of the standard goniometer, the rater removed the cover from the pointer and read the value together with the subject to exclude reading errors; the obtained value was entered into the blank. The angles, obtained by proper alignment of the paper strips, were drawn onto the appropriate sections of the blanks by using edges of the paper strips as rulers. If the arms of the standard goniometer or paper strips were inadvertently displaced during the evaluation, the measurement was repeated.