Resilience in the U.S. Air Force: A Study of Factor Structure Using the 10-Item CD-RISC and DRS-15

Background/Purpose: The past thirteen years of war have produced significant emotional and psychological strain in many military service members, with rates of PTSD among returning veterans reported to be between 17% - 20%.  However, it is noteworthy that the majority of service members do not develop negative psychological sequelae as a consequence of service.  This may reflect the presence of resilience, the ability to quickly adapt to and recover from risk and adversity.

Measurement of resilience remains complicated, but multiple psychometric scales have been developed and are widely used.  This study focuses on two resilience scales. First, a 10-item Connor-Davidson Resilience Scale (CD-RISC) that was normed with an undergraduate student population (74.4% female, average age 18.8 years).  Second, a reduced version of the Dispositional Resilience Scale (DSR), previously tested using Army Reserve medical units (45% female, average age 34 years).  The current study explores the underlying factor structures of these measures and their relevance within the U.S. Air Force.

Methods: The Community Assessment Survey was implemented to evaluate well-being within the U.S. Air Force.  Sample selection was based on duty location and consisted of Airmen (N=45,634, 75.2% male) from the three Air Force components: Active Duty (76.5%), National Guard (12.9%), and the Reserves (10.6%).  Response rates were 24%, 15%, and 13%, respectively.

A split sample methodology was employed to evaluate factor structure via exploratory factor analysis (EFA) followed by confirmatory factor analysis (CFA).  An independent samples t-test compared the two groups on the scale means; no significant differences were found.  The estimator for both the EFA and CFA was Maximum Likelihood and the rotation for the EFA was Geomin. 

 Results: An initial hypothesis indicated that the one factor structure previously found on the 10-item CD-RISC will not reflect a military population.  There is contradictory evidence between factor extraction (Eigenvalue=6.193) and the fit indices (RMSEA=0.108, CFI=0.937) for the 1-factor model, suggesting that it may not fit this sample.  

The DRS-15 was developed with three subscales (Commitment, Control, and Challenge) and was hypothesized to represent the current sample.  The suggested 3-factor solution (RMSEA=0.108, CFI=0.792), based on the developed subscales, did not perform well.  The EFA clearly pointed to a 4-factor solution, which was inconclusively supported in the CFA (RMSEA=0.088, CFI=0.878).

 Conclusions/Implications:  This study focused on assessing the fit of resilience measurement instruments to a military population, which will be key to understand and sustain the phenomena in service members.  An evaluation using the full 25-item CD-RISC is suggested, in order to develop a reduced scale more representative of Airmen.  Further evaluation of an interpretable 4-factor solution of the DRS-15, made up of Enthusiasm, Apathy, Rigidity, and Autonomy, should be encouraged.  Two of these factors are suggestive of the original concepts of hardiness, while the other two seem to represent the lack of hardiness.  The U.S. military is a unique subset of the U.S. population, appropriately normed and validated scales should be developed and used with them to provide the best quality information for assessment and intervention.