Specific language impairment and child care by a domestic helper: a case-control study in Chinese children.

OBJECTIVE To investigate the relationship between child care by domestic helper and specific language impairment (SLI). DESIGN Retrospective case-control study. SETTING A Child Assessment Center in Hong Kong that receives referrals from primary and secondary care settings. PARTICIPANTS We reviewed medical records of all new referrals younger than 5 years during a 4-year period (1999-2003) and compared children with SLI (cases) with those referred with other behavioral problems and assessed to have normal language and overall development (controls) using the Griffiths Mental Developmental Scale. Specific language impairment was defined as a language quotient more than 1 SD below the mean and below the general developmental quotient in children with normal general developmental quotient but without neurological or other organic diseases. RESULTS Four hundred ninety-six children were included (237 cases and 259 controls). The mean ages of cases and controls were 2.51 and 2.89 years, respectively. Boys predominated (cases = 73.4%, controls = 60.2%). The odds ratio (OR) of SLI for children cared for by a full-time domestic helper was 1.71 (95% confidence interval [CI], 1.06-2.77; P = .03), after adjusting for confounding sociodemographic variables. Male gender (OR = 1.91; 95% CI, 1.25-2.90), positive family history (OR = 2.70; 95% CI, 1.55-4.73), fewer siblings (P = .01), and lower paternal occupational status (P = .01) were also risk factors for an SLI. Childcare by a domestic helper was associated with a higher severity of an SLI in ordinal regression analysis (P = .048). CONCLUSIONS Childcare by a domestic helper is associated with increasing risk and severity of an SLI. Further studies are required to confirm the association and to evaluate whether avoidance of childcare by a domestic helper could be recommended for children with an SLI or prone to develop an SLI.