The reliability and validity of the icelandic parent development inventory for children from 36 months to 72 months

The construction of a 190-item developmental inventory for 36-72 month children based on parental report is described. In a sample of 508 mothers (Study 1), alpha-coefficients ranged from r =.72 to r =.90 for the eight subtests. A series of principal components analyses of the subtests’ standardized total scores at three age levels revealed two components in each case, one verbal and one motor. The two components accounted for 62.6% (36-47 month olds), 63.3% (48-59 month olds), and 64.3% (60-72 month olds) of the variance of the eight subtests’ standardized total scores. In a separate investigation of 27 mother-child dyads (Study 2), the inventory's subtests revealed satisfactory convergent-divergent validity when correlated with subscales of the Griffith's Mental Development Scale.