Validity of the activPAL3 activity monitor in people moderately affected by Multiple Sclerosis.

Walking is the primary form of physical activity performed by people with Multiple Sclerosis (MS), therefore it is important to ensure the validity of tools employed to measure walking activity. The aim of this study was to assess the criterion validity of the activPAL3 activity monitor during overground walking in people with MS. Validity of the activPAL3 accelerometer was compared to video observation in 20 people moderately affected by MS. Participants walked 20-30m twice along a straight quiet corridor at a comfortable speed. Inter-rater reliability of video observations was excellent (all intraclass correlations >0.99). The mean difference (activPAL3- mean of raters) was -4.70±9.09, -4.55s±10.76 and 1.11s±1.11 for steps taken, walking duration and upright duration respectively. These differences represented 8.7%, 10.0% and 1.8% of the mean for each measure respectively. The activPAL3 tended to underestimate steps taken and walking duration in those who walked at cadences of ≤38 steps/min by 60% and 47%, respectively. The activPAL3 is valid for measuring walking activity in people moderately affected by MS. It is accurate for upright duration regardless of cadence. In participants with slow walking cadences, outcomes of steps taken and walking duration should be interpreted with caution.

Development of a realistic method to assess wheelchair propulsion by disabled people.

Most wheelchair users cannot achieve the steady state of cardio-respiratory performance necessary for standard physiological testing of wheelchair propulsion on ergometers or treadmills. Furthermore "real life" wheelchair utilisation involves short bursts of energy expenditure around furniture and other obstacles. We have developed a method of measuring wheelchair mobility on a test circuit of varying tortuosity and report here our preliminary experience. The parameters of mobility measured included distance; time taken; resting, maximum and final pulses (using a portable monitor); time to recover to stable resting pulse; and perceived exertion using the Borg Scale. Average speed and physiological cost of wheelchair propulsion (PCWP) (the difference between maximum and resting pulse divided by average speed) were calculated. The reproducibility of the components of the method was demonstrated in studies on normal volunteers. The test was also shown to be suitable for use by a sample of disabled people and was used in comparative studies of conventional and a novel arm crank wheelchair in normal volunteers. The method described appears to be an accurate and objective method of assessing wheelchair propulsion suitable for use by disabled people. It can also form the basis of comparative studies of different methods of propulsion of wheelchairs.

Rehabilitation status in multiple handicap.

The Edinburgh Rehabilitation Status Scale (ERSS) was applied to 129 attenders at a day center for physical disability. All of the attenders had significant neurological impairment dating from birth or from infancy. Fifty-nine of the subjects (46%) had been diagnosed on conventional grounds as having mental handicap as well as physical disability. ERSS scores were compared with Barthel Index scores in all subjects and with PULSES profile in 50 subjects (27 physical disability alone, 23 combined with mental handicap). The ERSS scores clearly demonstrated significant differences in the level of disablement between the two groups in all four subscales as well as in total scores; the Barthel scores showed differences in self-care and total scores, and, to a lesser extent, in mobility. PULSES failed to differentiate the groups except in one of its subscales. The ERSS is a sensitive index of overall function and is useful in highlighting the additive effect of mental handicap and physical disability, a difference which may not be apparent when other assessment scales are used.

Rehabilitation status--the relationship between the Edinburgh Rehabilitation Status Scale (ERSS), Barthel Index, and PULSES profile.

A total of 364 patients attending day centres for the physically disabled had ERSS and Barthel scores recorded during the course of assessment. In addition, 100 of the patients had PULSES profile scores recorded. Correlation of total scores for all three scales confirmed that all three succeeded in measuring disability and all three were significantly related. There were, however, weak correlations between some of the individual subscales of each score, indicating that each of the assessment tools was measuring some dimensions of disability not adequately considered by the other scales. The results suggest that while progress is being made towards better measurement of disability and handicap, further refinement of these particular measurement tools is required.