Eighty-four high risk children were examined for suspected gastroesophageal reflux comparing 24-h esophageal pH measurements with ultrasound (US) scans with and without the use of color Doppler (CD). In 83.3% of the patients there was unequivocal agreement (reflux or no reflux) among all three techniques; 60.7% of the children showed reflux by pH-metry as compared to 51.2% by B-mode US and 59.5% by CD US. In 87% of patients there was agreement between pH-metry and B-mode US as compared to 94% between pH-metry and CD US. The sensitivity of reflux detection increased from 84.4% to 98% when CD was added to B-mode US. This improvement was thought to be due to the higher sensitivity of CD for rapid and small quantities of reflux. The small number of discrepancies between pH-metry and CD US is probably due to the inability of the former to detect neutral reflux of contents or short duration (< 30="" s),="" while="" cd="" us="" may="" miss="" some="" cases="" of="" acid="" reflux="" due="" to="" the="" short="" time="" of="" the="" examination="" (10="" min).="" the="" addition="" of="" cd="" increases="" the="" sensitivity="" of="" us="" for="" detecting="" reflux.="" this="" rapid,="" easy="" and="" reliable="" method="" can="" be="" used="" to="" screen="" high="" risk="" populations="" when="" reflux="" is="" thought="" to="" be="" the="" cause="" of="" respiratory="">