Employability assessment of computerized fatigue avoidance tool used with and without actigraphy among naval aircrew

Fatigue Avoidance Scheduling Tool (FAST) is a computerized fatigue prevention tool, which was developed based on a Bio-mathematical model called SAPTE (Sleep, Activity, Performance and Task Effectiveness). Similarly, actigraphy technology is used as a tool for sleep evaluation. This study was an attempt to assess the employability of FAST (both independently and integrated with actigraphy) for detecting operational fatigue by determining the 'Measures for diagnostic accuracy'.

103 pre-flight medical checks from 51 aircrew were evaluated to detect fatigue both clinically and by using objective measures (FAST and actigraphy integrated FAST). The 'measures of diagnostic accuracy' namely sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratio positive (LR +ve), likelihood ratio negative (LR -ve) and Youden's Index were determined and compared.

The diagnostic measures for FAST were: sensitivity (68.4%), specificity (92.8%), PPV (68.4%), NPV (92.8%), LR+ve (9.5), LR-ve (0.34) and Youden's Index (0.61). For actigraphy integrated FAST these values were: sensitivity (84.2%), specificity (96.4%), PPV (94.2%), NPV (94.4%), LR+ve (23.5), LR-ve (0.16) and Youden's Index (0.80).

The increase in sensitivity (from 68.4% to 84.2%), specificity (from 92.8% to 96.4%), PPV (from 68.4% to 94.2%), NPV (92.8% to 94.4%), LR+ve (9.5 to 23.5) and Youden's Index (0.61 to 0.80) indicated that actigraphy integrated FAST is a better screening tool in comparison to the independently employed FAST.