Table 2 Characteristics of the EMS, HABAM and PPME

Versions

1. Original [22].

1. Original [26,42]

2. Rasch refined [27]

1. Original [29]

Number of items

Seven

1. 27 in the original version

2. 22 in the modified version

1. Six items

Content

Lying to sitting, sitting to lying, sit to stand, stand, gait, timed walk (6 meters), functional reach.

MOBILITY: bedfast, chairfast, 2 person assist +/- aid, 1 person hands on +/- aid, 1 person standby +/- aid, with aid 8–50 m, with aid > 50 m, unlimited with aid, limited 8–50 m, limited > 50 m, unlimited.

TRANSFERS: total lift, 2 person assist, 1 person assist, 1 person pivot, 1 person hands-on, 1 person standby, independent with aid, independent.

BALANCE: impaired static sitting, stable static sitting, stable dynamic sitting, stable static standing, stable dynamic standing, stable transfer, stable with aid, stable ambulation.

Bed mobility, transfer skills, multiple stands from chair, standing balance, step-up and ambulation.

Time to complete

"No more than 5 minutes" [32]

Average of 2.6 (+/- 1) minutes [41].

Approximately 10 minutes [29]

8.6 minutes (SD = 3.6 minutes) [41]

Equipment requirements

A bed, chair, stop watch, walking aid if necessary, a space for a standardised 6 meter walk and a functional reach test.

A bed, chair and walking aid if required.

A bed, chair, stop watch, standardised step and gait aid if required.

Scaling method

One response is selected by the clinician administering the test for the 7 mobility tasks. Two items are scored from 0 – 2, four items are scored from 0 – 3 and one item from 0 – 4.

The original version of the HABAM is an ordinal measure. Interval level data is provided by the Rasch converted version of the HABAM.

The PPME has two scaling methods. The pass-fail PPME provides 2 response options (pass or fail) and the 3 level PPME provides 3 response options for each item (high pass, low pass or fail). Each response option is clearly defined [29].

Scoring

Each item score is summed to provide a total possible score from 0 to the maximum score of 20 which represents independent mobility. Scores under 10 are considered to represent "dependence in mobility manoeuvres", 10 – 13 to indicate "borderline in terms of safe mobility" and 14 or more to be "likely to be independent in mobility" [22].

The original version of the HABAM has a total score range of 0 – 24. One point is scored for each increment in ability. Higher scores indicate higher levels of mobility.

The Rasch converted HABAM has a broader interval score range of 0 to 26. A score is listed next to each item on the HABAM. Harder items have higher scores. The highest score obtained across the 3 sections of the HABAM represents the HABAM interval score. Higher scores indicate higher levels of mobility.

The pass-fail PPME provides a dichotomous scoring system for the 6 PPME items. Zero is scored for a fail. One point is scored for successfully completing each item. Items sum to obtain a maximum score of 6.

In the 3 level PPME scoring system, zero is scored for a fail, one point for a low pass and two points for a high pass. The total score range is 0 – 12.

Floor and ceiling effects

A ceiling effect was identified for community dwelling older adults who had experienced a single fall in the previous 6 months, "approximately 50% of single fallers scored 19 – 20" [30].

Twenty healthy 81 to 90 year old women all scored the highest possible score of 20 on the EMS [22].

A ceiling effect was identified in an older acute medical patient population. Approximately 25% of patients scored the maximum possible score at hospital admission [27].

An absence of floor and ceiling effects has been reported for the 3 level scoring system [29].