234958 Comparison of Two Length Measurements: Lengthboard and Paper Barrier

Wednesday, November 2, 2011

Amethyst Cureg, MD, MPH, FAAP , Maternal Child and Family Health Services Branch, County of San Diego Health and Human Services Agency Public Health Services, San Diego, CA
Nancy Starr, MPH, RDH , Division of Child and Community Health, University of California San Diego, San Diego, CA
Lorri Freitas, MPH , Public Health Epidemiology, County of San Diego Health and Human Services Agency, San Diego, CA
Background: A calibrated lengthboard is recommended to measure length for children under 24 months of age. Physicians continue to use the disposable examination table paper and a non-stretchable tape to measure the distance between hand drawn lines to measure length. This study compares the intra-rater and inter-rater reliability and the differences between the two methods. Methods: A sample of 140 well children 2 weeks to 36 months of age was measured. Using standardized protocols and equipment recumbent length was measured twice each time by a pair of trained examiners using the lengthboard. Then, the length was measured using the paper method twice. Examiners were blind to their own and each other's measurements. Results: Study demonstrated high intra-rater and inter-rater measurement reliability for both methods. There was a statistically significant difference between measured length using the lengthboard and paper (p < .001), with a difference of up to 6 inches between two methods, and a mean difference of .65 inch using the Wilcoxin Signed Ranked Test. On the average, measurements were longer when the paper method was used. Conclusions: Study indicates that a high degree of reproducibility can be achieved using either method by trained staff. However, there is a very significant difference (p<. 001) of up to 6 inches between the two methods. This suggests that the recommended lengthboard is the more reliable method of measurement. Use of the paper method, especially in a busy practice setting can magnify errors and affect a child's percentile placement on the growth chart.

Learning Areas:
Provision of health care to the public

Learning Objectives:
1. Compare the intra-rater and inter-rater reliability of length measurements using two recumbent measuring techniques, the lengthboard and paper barrier. 2. Demonstrate if a statistically significant difference of measurements is obtained between the two techniques.

Keywords: Child Health, Research

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am qualified to present because I oversee the maternal and child health programs in the County of San Diego Health and Human Services Agency.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.