Association between physiological and perceptual heat strain while wearing stab-resistant body armor

Agreement between measured and self‐reported physiological strain in males and females during simulated occupational heat stress

“…For example, while other studies reporting similar results to the present study have concluded that the PeSI is an acceptable predictor of PSI, these reports have predominantly focused on the correlation between measures, 16,18,19,21 which may be inappropriate for evaluating agreement between indices. 35 As such, we assessed our data via Bland-Altman analysis.…”

“…35,36 Of note, we observed similar findings (as evidenced by mean bias and LoA) to prior studies that have assessed agreement via Bland-Altman analysis. 10,20,21 That said, in these studies 10,20,21 the respective authors have shown that PeSI has discriminatory utility to differentiate between high and low levels of physiological strain when wearing personal protective equipment, whereby PeSI was able to accurately predict or conservatively (over) estimate physiological strain >75% of the time. 10,20,21 Thus, while PeSI may be suitable to dichotomize between broad levels of physiological strain (i.e., low or high), the wide LoA 10,20,21 highlight the variability in how individuals perceive physiological strain.…”

“…10,20,21 That said, in these studies 10,20,21 the respective authors have shown that PeSI has discriminatory utility to differentiate between high and low levels of physiological strain when wearing personal protective equipment, whereby PeSI was able to accurately predict or conservatively (over) estimate physiological strain >75% of the time. 10,20,21 Thus, while PeSI may be suitable to dichotomize between broad levels of physiological strain (i.e., low or high), the wide LoA 10,20,21 highlight the variability in how individuals perceive physiological strain. While the PeSI may therefore provide a rough approximation of the level of physiological strain, it likely cannot be used directly as a surrogate marker of PSI in young males and females.…”

“…Previous investigations have promoted the PeSI as an efficacious method to reflect physiological strain under a wide range of environmental conditions; 10,[15][16][17][18][19][20][21][22]34 however, recent work 10,20,21,34 has shown these relationships, while encouraging, to be highly variable.…”

“…8 The PeSI has been suggested to be reflective of physiological strain across a range of environmental conditions, workloads, work tasks, field settings, and clothing ensembles. 10,[15][16][17][18][19][20][21][22] For the PeSI to accurately reflect PSI, TS, and RPE must reflect core temperature and HR. 10 Thus, in situations where differences between perceived and actual (physiological) strain exist, the PeSI will not accurately reflect the true level of strain experienced.…”