Statistical validation of the Positive and Negative Occupational Stress Inventory.

With the emergence of positive psychology a decade ago, focus on psychology has shifted from human weaknesses to human resources. In work psychology, researchers are interested not only in negative responses to professional demands, but also in positive responses.

The Positive and Negative Occupational Stress Inventory (PNOSI) was designed to measure both constructs with separate items. This idea was later confirmed by Schaufeli, Salanova, Gonzalez-Roma & Bakker (2002) , according to which positive and negative occupational stress are distinct constructs with different causes and consequences, and should be measured with different items.

We first asked 150 psychology students to generate words describing positive and negative stress. This enabled us to elaborate 34 items relating to emotional, cognitive, behavioural and physiological stress manifestations.

These items were administered to 152 workers. Exploratory factor analyses showed a two-factor underlying structure. The first factor consisted of eleven items measuring Negative Occupational Stress (NOS), the second consisted of eight items measuring Positive Occupational Stress (POS).

This structure was tested on another sample of 4666 workers. Exploratory factor analyses confirmed the two-factor structure. The two subscales have good psychometric properties, α = .87 and α = .84 for NOS and POS, respectively.

Results show that the PNOSI can be considered a valid tool for measuring positive and negative sides of well-being at work. Further confirmatory factor analyses should first try to confirm and replicate this structure on different samples. Second, convergent and discriminant validity with related concepts, such as burnout and engagement, should also be tested.