Objective To determine whether facial growth at five years is different for children with a right versus left sided cleft lip and palate.

Design Retrospective cohort study

Setting Nine UK cleft centres

Patients Patients born between 2000-2014 with a complete unilateral cleft lip and palate (UCLP)

Main outcomes measure 5-Year-Old’s Index scores

Results 378 children were included. 122 (32%) had a right sided UCLP and 256 (68%) had a left sided UCLP. 5-Year-Old’s index scores ranged from 1 (good) to 5 (poor). There was a higher proportion of patients getting good scores (1 and 2) in left UCLP (43%) compared to right UCLP (37%) but there was weak evidence for a difference (Adjusted summary odds ratio 1.27, 95% CI 0.87 to 1.87; P=0.22).

Conclusions Whilst maxillary growth may be different for left versus right sided UCLP, definitive analysis requires older growth indices and arch forms.

The authors have declared no competing interest.

This study did not receive any funding

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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Ethical application assessed by the North West - Greater Manchester Central Research Ethics Committee (REC Ref: 18/NW/0536, IRAS: 225282, Research Registry UIN: 4068). Ethics approval was given.

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Ethical application assessed by the North West - Greater Manchester Central Research Ethics Committee (REC Ref: 18/NW/0536, IRAS: 225282, Research Registry UIN: 4068). Ethics approval was given.

All data produced in the present study are available upon reasonable request to the authors