The Standard Shiftwork Index: A battery of questionnaires for assessing shiftwork related problems

The lack of standardization in shiftwork research has been recognized. In response, a battery of self-report questionnaires has been developed, which might usefully be employed in assessing the impact of different types of shift systems on large groups of individuals. The scales included reflect the most pertinent issues within shiftwork research, and were chosen on the basis of being both relatively short, easy to administer, and having good psychometric properties. The scales fall broadly into three main categories: outcomes, relating to the actual problems experienced by the individuals concerned; modifiers, relating to those differences between individuals which may serve to moderate the impact of shiftwork; and general, including work context and shift system details. Suggestions as to how the questionnaires might usefully be employed are offered. Based on the results of a large sample of nurses and midwives, and a second sample of industrial and service workers, the present paper offers: a set of normative data against which comparisons with other shiftworking groups can be made; the identification of the relationships that exist between the outcome and modifier variables; and evidence of the sensitivity of the scales in differentiating between groups of shiftworkers on different types of shift systems.