Table 1 Overview of the functional outcomes. Each functional ability is described by the corresponding outcome and tool used to assess the ability, its test quality criteria, conduction and the (positive) decision criteria

Joint position sense

Absolute angle reproduction error [degrees]

Intertial motion unit

Unknown,

ICC = 0.31–0.82 (sitting) and 0.17–0.75 (prone) [21]

Start point see Flexion. A target angle in flexion RoM must be reached and reproduced after a 3 s break

Dynamic Balance

Composite score

Y-Balance test (imprinted on a carpet or affixed on the floor)

Good interrater test–retest reliability, acceptable level of measurement error [22]

Single-(test)leg standing, other leg must be moved anterior, posterior later and posterior medial as fast as possible without losing postural control. Composite score is calculated by adding all three single values divided by three times the limb length, this all multiplied by one hundred

Vertical jumps and hops measurement

Knee displacement [cm]

Drop Jump,

Intertial motion unit

ICC = 0.93 [23]

Bipedal hip-width stance on a box with a 32 cm target-height. A bipedal drop jump follows: frontal step – drop – reactive jump with the shortest possible ground contact time

Hopping height [mm]

Vertical hop,

intertial motion unit

ICC = 0.89 -0.97 [24];

Average error with intertial sensors: -0.4 to 2.2 cm [25], ICC = .98

Unipedal stance on the ground, one-legged counter movement jumps

horizontal jumps and hops

Time to completion [seconds]

Speedy jump,

intertial motion unit

ICC = 0.792–0.825 [26]

A small trail must be passed as fast as possible in one-legged hops

Number of hops in 30 s [n]

Side hops

intertial motion unit

Unknown

Participants have to hop the participants hop over laterally (to the foot’s respective side) over a square on the floor with 30 × 30 cm edge length with hands on their hips as fast as possible [27] (article in German)

Hopping distance [cm]

Single leg hop for distance

The measurement properties for the SLHD are excellent, reliability is ICC = 0.97 (CI 0.9–0.99) and the standard error of measurement is 3.5% [28]

The participants stand on one leg with the toes behind the rear line of the square. He/she then hops as far as possible and has to land in a controlled manner. The whole hop must be performed one-legged