An error occurred in the September/October 2003 issue of Nursing Research, 52 (5), in the article entitled, "Development of behaviors in preterm infants: Relation to sleeping and waking," by Holditch-Davis et al., pages 307-317. In Table 5 on page 315, one number was inadvertantly written with the wrong sign. The parameter for the postconceptional age effect for the difference between active sleep with REM and nonsleeping should have been -0.18, rather than 0.18 as it was published. As a result, the final sentence on page 312 which finishes on page 313 should have read, "Although the probability of having hiccups did not differ between nonsleeping and the active sleep states, these differences were greater at younger ages." All other sentences in the article are correct, including all parts of the discussion section.