Hearing evaluation to 654 cadet pilots under PLA versus US army medical standards

Objective To analyze the hearing examination data of cadet pilots according to the hearing standards of PLA and US army, learn the differences of hearing standards between the two armies, and provide suggestions for the revision of medical standard of hearing in the cadet pilots. Methods The first hearing examination data of cadet pilots (17-20 years old) were collected. The hearing data at high frequency, middle-low frequency and general hearing condition were determined according to the medical standards of PLA and of the US army respectively. The numbers of qualified and unqualified cases were counted respectively. Results Totally 654 male cadet pilots were examined. The results using PLA standard were consistent with that using US army's standard in high-frequency screening (Kappa=0.53, P＜ 0.05), middle-low frequency screening (Kappa=0.66, P＜ 0.05) and general hearing screening in some degree (Kappa=0.56, P＜ 0.05). There was a tendency that the qualified cases determined by PLA's selection standard tend to be qualified too when the US army's standard was used. In high-frequency hearing screening, 606 of 654 cadet pilots were qualified, and 18 were unqualified under the two hearing standards. Thirty cadet pilots were qualified under the PLA's standard, but they were unqualified under the US army's standard. The number of cadet pilots that were unqualified under the PLA's standard but qualified under the US army's standard was 0. In middle-low frequency hearing screening, 630 of 654 cadet pilots were qualified, and 12 were unqualified under the two hearing standards, 3 cadet pilots were qualified under the PLA's standard, but unqualified under the US army's standard, 9 cadet pilots were unqualified under the PLA's standard, but qualified under the US army's standard. In the general hearing screening, 582 of 654 cadet pilots were qualified and 30 were unqualified under the two standards, 33 cadet pilots were qualified under the PLA's standard, but unqualified under the US army's standard, 9 cadet pilots were unqualified under the PLA's standard, but qualified under the US army's standard. In the high-frequency hearing screening, thedenial rate was higher under US army standard than that under PLA standard (7.34% vs 2.75%, χ²=28.03, P＜ 0.05). There were no significant differences between the denial rates under US army's standard and that under PLA standard in the middle-low frequency hearing screening (2.29% vs 3.21%, χ²=2.08, P＞ 0.05). In the general hearing screening, the denial rate under the US standard was higher than that of the PLA with statistically significant difference (9.63% vs 5.96%, χ²= 13.71, P＜ 0.05). Conclusion The hearing standard in medical selection for cadet pilots at high frequency in the US army is stricter than that in the PLA, meanwhile the standard at middle-low frequency in the US army is broader than that in the PLA. The US army's and the PLA's standard have their own emphases respectively. In comparison, the US army's hearing selection standard is stricter, more specific and well-founded.