Reliability of a field based 2D:4D measurement technique in children

Validation of digit-length ratio (2D:4D) assessments on the basis of DXA-derived hand scans

“…In addition to the importance and high relevance of 2D:4D research in sport the results of our study were in line with 2D:4D values found in studies performed by Manning and Hill [ 37 ] and Manning and Taylor [ 6 ]. The intrarater and interrater variances of 2D:4D using techniques other than DXA showed similar results as well (e.g., [ 13 , 39 , 40 ]). Allaway [ 13 ] assessed the level of intrarater and interrater reliability when evaluating 2D:4D using four different techniques: direct finger length measurements, photocopies, printed scanned images, and computer-assisted image analysis.…”

“…The ICCs of interrater reliability were 0.89 by computer-assisted, 0.86 by photocopies, 0.80 by direct measurements, and 0.76 by printed scans. Ranson, Taylor, and Stratton [ 39 ] showed an excellent interrater ICCs reliability of 0.95 (0.92–0.97) and a very good to excellent interrater ICCs reliability of 0.90 (0.83–0.94) using photographs as an imaging technique. A longitudinal study with Jamaican children found interrater ICCs of 0.951 (left hand) and 0.940 (right hand), respectively, and four years later, ICCs of 0.977 (left hand) and 0.971 (right hand), respectively, were reported using direct measurements [ 3 ].…”

Digit ratio (2D:4D) and physical fitness (Eurofit test battery) in school children

“…From these two sets of measurements 2D:4Da and 2D:4Db were calculated. The Pearson's correlation coefficients of 2D:4Da compared to 2D:4Db was high (r = 0.95), as was the intra-class correlation (r = 0.90), whereas the coefficient of variation (CV) was very low (0.9%) [21]. Therefore, we concluded that our measurements of 2D:4D reflected real betweenindividual differences.…”

“…All fitness testing was performed on the same day of the week between 09:00 and 15:00 h. Participants undertook a standardised 10-minute warm up consisting of dynamic stretches to music. Right hand 2D:4D was measured using a digital camera (Sony Cyber-shot, Singapore) and Adobe Photoshop software (Adobe systems, San Jose, CA) following the procedures outlined by Ranson et al [21]. All the photographs were coded to ensure that the researcher measuring digit length was blinded to the fitness scores and the appearance of the individual child to reduce experimenter bias [22].…”

Relationships between the second to fourth digit ratio (2D:4D) and game‐related statistics in semi‐professional female basketball players

“…Unlike with other indirect methods (eg, photocopies or scans) of capturing images of digits, this method does not require that the digits be placed downward onto a glass surface, which may distort digit tips and influence 2D:4Ds (Ribeiro, Neave, Morais, & Manning, 2016). This method demonstrates very good repeatability and validity (vs. manual measurements) (Allaway, Bloski, Pierson, & Lujan, ; Hull et al, ; Ranson, Taylor, & Stratton, ). Prior to analyzing the study data, intra‐tester and inter‐tester repeatability were assessed using a sample of 20 adults.…”