Questioning the stability of sense of coherence - The impact of socio-economic and working conditions in the Canadian population

Background. Much debate exists about the stability of the sense of coherence measure. This study examined changes in sense of coherence (SOC), and the variables associated with these changes, over a 4-year period, in a representative sample of the Canadian labour force (n = 6,790). Methods. Two methods were used to assess change in SOC: (1) Change outside of that which could be considered as indistinguishable from measurement error, and (2) Change of more than 10%, which was originally proposed by Antonovksy, the scales designer. Results. Over the study period, 35.4% of the population reported changes in SOC outside the range we consider possible due to measurement error, with 58% reporting change greater than 10%. Unskilled occupations were associated with declines in SOC, with household income demonstrating a curvilinear relationship with decline in SOC in the female population only. None of the variables used predicted increases in SOC. Conclusions. Given the degree of change in SOC, and the representativeness of the study sample, we suggest that SOC has a large state component. Given this lack of stability, we recommend caution if using the SOC to represent a stable global orientation within a causal context.