Diver adaptability during a nitrox saturation dive at 7 ATA

The major objective of this study was to demonstrate the advantages of transforming raw scores to ipsative form (deviation scores calculated around each subject's mean), particularly in diver research characteristically involving small subject samples in a self-control design. Measures of reaction time, response accuracy, anxiety, hostility, and depression were obtained from three U.S. Navy divers (Ss) during a nitrox saturation dive at 7 ATA (bottom time 7 days). It was argued and to some extent demonstrated that normative (interindividual) statistics obscure individual differences which are clearly delineated with the scores in ipsative form. Further, this score transformation allowed for meaningful between-Ss (same measure) and between-measures (same S) comparisons. These relationships could not be demonstrated with the scores in normative form. Application of P-technique of factor analysis within each S's arrays of data suggested that the characteristic adaptive patterns of two Ss in this study reacted to the pressure-stress by directing affect inward; for the third S, affect was directed outward. However, none of the 20 scales from the Minnesota Multiphasic Personality Inventory clearly discriminated among the three adaptive types.