Abstract
Objective: To propose objective criteria of cutoff heights for still-growing youth by examining current criteria and identifying their short comings Study Design: Observational study Place and Duration of Study: Initiated in 1998 in schools run by the Armed Forces of Pakistan; a civilian school added in 2011 Subjects and Methods: Primary-school students’ heights and masses were measured, to least counts of 0.1 cm (1998-2011); 0.01 cm (2012-2015); 0.005 cm (2016 to date) and 0.5 kg (1998-2011); 0.01 kg (2012-2015); 0.005 kg (2016 to date), respectively, during morning hours, implementing standardized protocols (ethical guidelines followed, students undressed to underpants, equipments calibrated daily, measurer reproducibility documented), and modeled to compute estimated-adult heights, estimated-adult masses, height and mass percentiles, optimal masses, estimated-adult BMIs (body-mass indices). In order to deal with extreme cases, CDC Growth Tables were extended using mathematical-statistical techniques to include 0.01th, 0.1th, 1st, 99th, 99.9th and 99.99th percentiles. Scaled percentiles of height and mass, suitable for the Pakistani population, were generated from CDC percentiles of height and mass by fitting parabolic curves with the condition that 40th CDC percentile (of height/mass) corresponds to 50th scaled percentile (of height/mass). Results: Data of 1185 students were analyzed. Mean age was (8.08 ± 2.23) years. Using Extended CDC Growth Tables, height percentiles corresponding to cutoff heights for induction into the Armed Forces of Pakistan were determined as 2.72 (for males) and 19.36 (for females). Conclusion: Induction criteria for still-growing youth (boys less than 21-year old and girls less than 19-year old) should be based on percentiles rather than measured heights.
