Clinical Decision Rule Identifies Children Who Need Head Imaging

A new clinical decision rule helps emergency room physicians determine which young children require radiography for assessment of minor head injuries, according to a study published in the Canadian Medical Association Journal (CMAJ).

Researchers from Canada performed a prospective cohort study to develop and validate a clinical decision rule to help ER physicians identify children who present with minor head trauma that benefit from skull imaging. The first phase developed the decision tool and the second phase confirmed the tool.

A total of 1,667 children under the age of two who had a minor head injury, but were not considered to be at high risk for clinically important traumatic brain injury (Glasgow Coma Scale score < 15, altered level of consciousness or palpable skull fracture), were included in the study. Most injuries were caused by a fall. The first phase of the study included 811 children. Forty-nine children had a skull fracture. For the second phase, 856 children (44 with skull fractures) were included.[[{"type":"media","view_mode":"media_crop","fid":"42381","attributes":{"alt":"","class":"media-image media-image-right","id":"media_crop_120027632776","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"4573","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"height: 107px; width: 160px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"©Andrey Burmakin/Shutterstock.com","typeof":"foaf:Image"}}]]

Skull radiography was ordered for 645 children (38.7%), 291 (35.9%) in the derivation cohort and 354 (41.4%) in the validation cohort. Of the remaining children, 991 (507 in the derivation cohort and 484 in the validation cohort) were followed up by telephone at four weeks. None of the children experienced complications from their head injury.

The two predictors identified through recursive partitioning were parietal or occipital swelling or hematoma and age less than two months. “The rule had a sensitivity of 94 percent and a specificity of 86 percent in the derivation phase,” the authors wrote. “During the validation phase, 856 participants (44 with skull fracture) were recruited. The rule had a sensitivity of 89 percent and a specificity of 87 percent during this phase.”

The researchers found that four of five missed fractures were in children who were younger than four months old. They noted that modifying the rule to include children who were three months old and younger would increase the sensitivity to 98% and lower the specificity to 82%.

By implementing the rule, the number of radiographs performed on this population would have dropped by approximately 60%, the authors concluded.

"The authors provide front-line clinicians with objective decision-making criteria, more helpful than 'observation versus CT,' Peter Gill, MD, of The Hospital for Sick Children and University of Toronto in Ontario, and Terry Klassen, MD, of the University of Manitoba in Winnipeg.

"But perhaps most important, the rule is simple: in children less than two years old with a minor head injury who do not meet the criteria for a CT scan, perform a skull radiograph if they are less than two months old or they have parietal or occipital swelling. If only all clinical decision rules could be this simple," they concluded.