Table 1

Data extracted from the eligible studies regarding evidence-based classification in wheelchair sports.

StudyPurposePara Sport /SampleEvaluation of the TestQuantification ToolsQuantified VariablesMain results for classification
(Borren et al., 2014)Analyze wheelchair rugby athletes while performing different passing techniques and compare athletes from different classes.Wheelchair Rugby / 15 athletesChest pass. Impact pass. Overarm pass. Sidearm pass.Kinematic Analysis. Throw force, power, and speed for each one of the passing techniques.The group without triceps function had an average pitch of 3.5 m and the group with triceps function had an average pitch of 8 m. In this way, athletes with higher classes had better results than athletes with low legs. In addition, the study showed that the current classification had a good correlation with what was found in the study.
(Hyde et al., 2016)Investigate the influence of the assistive pole, seat configuration, and upper-body and trunk strength during sitting throws in athletes with spinal cord injury (SCI).Wheelchair Rugby, Wheelchair basketball and World Para Athletics / 10 athletes
Seated throwing and strength tests.kinematic analysis;  Grip Strength; Dynamometer.
3D kinematic data were collected (150 Hz) for both conditions using standardized and self-selected seat configurations. Dominant and nondominant grip strength were measured using a dynamometer, and upper-body and trunk strength was measured using isometric contractions against a load cell.The athletes performed better when they used an assistive pole. The seat configuration had no influence on performance. Grip strength measures were significantly correlated with the speed of the throw. These results contribute to the investigation of the evidence-based classification.
(Altmann et al., 2016)Assess the impact of trunk impairment, using the Trunk Impairment Classification (TIC) on performance.Wheelchair rugby / 55 athletes: – 21 with TIC score 0. -13 with TIC score 0.5. – 11 with TIC score 1.0. -10 with TIC score 1.5.
10 m sprint test,  Turn test. Tilt test. Maximal initial acceleration test. Hitting test.
Infrared sensors;  A sensor (AMR Sports).
10 m sprint test: time to perform the test [s]. Turn test: time to cover the 10 m distance [s]. Tilt test: tilt height [mm]. Maximal initial acceleration test [m/s2]. Hitting test: Distance [m] needed to reach a difference of 81 cm between athletes per TIC score; and, sprint momentum [kg*m/s].
The study demonstrated that trunk impairment has an impact on acceleration in the first 2 meters, so we can infer that athletes with limited trunk impairment are more proficient in wheelchair rugby than athletes with severe trunk impairment.
(Santos et al., 2017)They evaluated the influence of the classification of rugby in a wheelchair (WR) and the competitive level in the function of the trunk using seated stability limits (LoS).Wheelchair rugby / 28 athletes divided into three groups according to national or international competition following IWRF categories: a low-point group, comprising 0.5–1.5-point players, =8; a mid-point group, with 2.0–2.5-point players, N=14; and a high-point group, with 3.0–3.5-point players, N=6.
Participants had to sit down on a wooden block, leaning and stretching their bodies as widely as possible towards eight pre-defined directions. Research arranged all eight directions in a diamond shape, separating them by 45-dregree intervals.Force platform. Seated limits of stability (LoS) were computed as the area of ellipse adjusted to maximal CoP excursion achieved in each one of the eight directions.High point players had a higher limit of seated stability (LoS) when compared to low point players. LoS can be a valid form of assessment for trunk impairment, which contributes to evidence-based classification.
(Connick et al., 2017)Validate isometric strength tests and analyze whether strength measures can be used to classify athletes.Wheelchair-Racing / 32 athletes

Maximum Isometric strength tests: arm extension (right and left), combined arm extension + trunk flexion, isolated trunk flexion combined forearm pronation with grip strength (right and left). Wheelchair racing performanceS-type load cell;  Musclelab unit;  Video camera;  Dartfish Prosuite; T-dynamometer;  Laser devices. 

Isometric strength tests: peak force Racing performance: maximum speed (0–15 m) (m/s), maximum speed (absolute) (m/s).
All six strength tests correlated with performance (r = 0.54-0.88). Through cluster analysis, 4 classes were identified and for 6 athletes the allocation differed from their current class, classes T53 and T54 had no significant differences in any of the performance results. This demonstrates that perhaps the class system adopted for this sport needs to be revised. These results contribute to the classification based on evidence of wheelchair racing.
(Squair et al., 2017)Establish an ideal autonomic test protocol to predict cardiovascular capacity during wheelchair rugby competition.Wheelchair Rugby / 26 athletes.

Neurological level and completeness of injury. Autonomic completeness of injury. Resting hemodynamic. Orthostatic challenge test. Cold-pressor test. In-competition exercise performance.
International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI); Sympathetic skin responses (SSRs) electrodes  one-lead electrocardiography; Automated BP cuff.
Motor scores for upper and lower limbs (on a scale of 0-5). Sympathetic skin responses (on a scale of 0-2). Measure SSRs of median nerve stimulation. Resting hemodynamic (HR, SBP). Orthostatic intolerance. Cold-pressor test = changes in BP and HR with temperature change. Peak HR during competition

Changes in PAS during the orthostatic challenge test and foot and hand TCP correlated significantly with cardiovascular response in competition. The results demonstrate the importance of incorporating cardiovascular capacity assessments in the classification to ensure more equitable competitions.
(Altmann et al., 2017)Evaluate the relationship between impaired trunk strength and performance in Wheelchair Rugby through the concept of “natural classes”.Wheelchair Rugby and wheelchair basketball / 27 athletes
Maximum isometric trunk muscle strength test (three directions: forward, to the left and to the right). Activity limitation: tilt test (lifting the non Fixed wheel from the floor by using their legs), and trunk acceleration test (perform maximum acceleration, maintaining speed for 3 to 5 m and then decelerate)Load cell; Cheetah LMT.

Maximum isometric trunk muscle strength test: mean isometric force (N). Tilt test: The height of the tilt (difference between H1 and
H0 [mm]). Acceleration test: Displacement
of the wheelchair (m) and time (s).
The inclination height had significant correlations with the left force, right force, frontal force and acceleration. The cluster analysis demonstrated that at least one cutoff point in performance, supporting the concept of “natural classes”. The Strength of the trunk plays a fundamental role in the classification of this sport.
(Van der Slikke et al., 2018)Evaluating whether measurements with inertial sensors could offer an alternative point of view for classification.Wheelchair Basketball / 76 athletes

First group: match. Second group: standardized field test.

Inertial sensors.Six key outcomes of wheelchair performance: Average speed (m/s). Average best speed (m/s). Average acceleration (m/s²). Average rotational speed (m/s²). Average best rotational speed (°/s). Average rotational acceleration (°/s)
Low class athletes showed lower performance results when compared to middle class athletes, however there were no differences between middle class athletes and high class athletes. The Two Step Statistical Method revealed two clusters, one of low class and another of middle / high class, the most important predictors of the model being the results of the forward movement. These results demonstrate the possibility of revising the basketball classes.
(Mason et al., 2020)Validate and test the reliability of a battery of uniarticular isometric strength tests, for the evidence-based classification in wheelchair rugby (WR).Wheelchair Rugby / 20 athletes (WR) and 30 healthy participants
able-bodied (AB)

Seated participants performed a battery of isometric strength tests: shoulder flexion and extension and elbow flexion and extensionS-type load cell; MuscleLab.

Peak isometric force (N)The battery of tests revealed that there is an increase in flexural strength around the shoulder and elbow. In addition, the test battery achieved good reliability. Thus, the results suggest that the battery of tests can be used to safely infer the impairment of strength in WR athletes. Supporting an evidence-based classification system.
(Van der Slikke et al., 2020)Apply the Wheelchair Mobility Performance Monitor (WMP) to athletes to identify factors and results that have an impact on classification and performance.Wheelchair basketball (WB), Wheelchair tennis (WT) and Wheelchair rugby (WR) / 29 WB athletes; 32 WR athletes; 15 WT athletes
The athletes were evaluated during competitive matches in each para sportInertial sensors.Average speed (m/s) Average best speed (m/s) Average acceleration in the first 2 m from standstill (m/s²) Average rotational speed during a curve (m/s) Average best rotational speed during a turn on the spot (m/s) Average rotational acceleration (m/s²).The WB achieved better performance results in the VMP, followed by the WT and finally the WR. In all sports, a substantial amount of time, ~ 10% was spent at reverse speed. Through the results found in this work it was possible to identify that intensity is an important factor for WB training programs, as well as maneuverability for WT and level of disability for WR.
Caption: this table presents the main information of the articles that were selected for this review.