Assessing psychological health in midwifery practice: a validation study of the Four-Dimensional Symptom Questionnaire (4DSQ), a Dutch primary care instrument.

OBJECTIVE

the Four-Dimensional Symptom Questionnaire (4DSQ) is a validated self-report questionnaire, developed for general practice to assess the level of distress, somatization, depression and anxiety among patients. This study evaluated the validity of this instrument for midwifery practice by differential item functioning analysis.

DESIGN

cross-sectional.

SETTING AND PARTICIPANTS

the focal group consisted of clients of 15 primary care midwifery practices in The Netherlands (n=478). The reference group consisted of Dutch female primary care patients, matched for age (n=478).

MEASUREMENTS AND FINDINGS

Differential item functioning (DIF) was assessed by ordinal regression and the Mantel Haenszel method. The impact of DIF was measured by linear regression. The depression scale was free of DIF. The somatization, distress and anxiety scale contained items with DIF. Because of DIF, pregnant and postpartum women had on average 1-2 points lower predicted scores on the somatization scale and 1 point lower scores on the anxiety scale. On the distress scale the midwifery group had 1-2 higher predicted scores.

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

the 4DSQ is a valid instrument for casefinding of psychological disease in midwifery practice, provided cut-off scores of the distress, anxiety and somatization scale be adapted.