The Survey of Well-being of Young Children


The Developmental Milestones questions include indicators of fine and gross motor, language, social, and cognitive development. Items were chosen based on a review of a large number of instruments as well as consultations with experts in the field. Based on clinical experience, we observed that parents often describe behaviors that approximate a given milestone before their child manifests the full behavior. To reflect this, we adopted a prototypical scoring systems with three response options where 0 = not yet; 1 = somewhat, and 2 = very much.

The validity of the Developmental Milestones was assessed via comparison with: (a) the Ages & Stages Questionnaire, 3rd Edition (ASQ-3), a 30-item developmental screening instrument, and (b) previous diagnoses of developmental delay as indicated by parent report. While the finalized set of Developmental Milestones is still in development, initial data are encouraging. Overall, the Developmental Milestones predicts clinical ASQ-3 scores with sensitivity of .81 and specificity of .76 and parent report of diagnoses with sensitivity of .78 and specificity of .73. A study designed to replicate these results is ongoing. For more complete information on the ASQ-3, you can consult their website at

Our research found that the 2- and 60-month forms have less robust validation data to support their use for scoring as compared to the other age forms. Hence, we urge caution in interpreting total scores for the 2-month and 60-month forms. They are useful for surveillance, but the scores should be considered imprecise. For this reason, we excluded these forms from our primary scoring table (see Milestones Scoring Guide).


  • Developmental

Age range: 

  • There is a different 10 item set of Milestones items for every Age-Specific SWYC Form
  • The Milestones are on top of the front side of each Age Specific SWYC Form


  • Each form includes 10 items. Score each item using these values. "Not Yet" corresponds to "0", "Somewhat" to "1", and "Very Much" to "2". Missing items count as 0. Add up all 10 item scores to calculate the total score. 
  • Use the hand scoring guide or the Excel-based "SWYC Form and Milestones Calculator" to see if the score falls above or below the scoring thresholds (see download above).
  • Note that no scoring thresholds are available for the 2 and 60 month forms at this time. See the scoring guide and SWYC Manual for more information

The SWYC and the information on this site are not designed to and do not provide medical advice, professional diagnosis, or treatment. The information and any reference materials posted here by Tufts Medical Center, Inc. are intended solely for the information of the reader. Such information is NOT intended to replace consultation with a qualified medical professional. The SWYC is copyright © 2010 Tufts Medical Center.