The North Queensland ‘Sun-Safe' Clothing Study: effectiveness of sun-protective clothing in preventing or delaying the development of pigmented moles in early childhood.

This prospective cluster-randomised controlled intervention trial involved children aged 1-35 months-old (at baseline) attending intervention daycare centres (n=13) wearing sun-protective study garments and legionnaire hats while at daycare. All daycare centres in the intervention group were given sufficient numbers of the following study garments (in a range of sizes) to ensure that they could clothe all children in attendance at the centre in our study garments each day: 1) Ultraviolet Protection Factor (UPF) 50-plus legionnaire hats; 2) 100% cotton T-shirts offering "very good protection" (i.e. UPF 25-39 blocks between 96 percent and 97.4 percent of erythemally effective UVR) with sleeves 21 percent longer than T-shirts made to Australian standard sizing; 3) water-resistant nylon taslon shorts designed to cover the legs to below the knees and made of UPF 40 rated fabric (i.e. blocks at least 97.5 percent of erythemally effective UVR) providing "excellent protection". 4) water-resistant UPF 40 rated nylon taslon long-sleeve shirts for use during outdoor water-play. Study clothing was used and maintained (laundry service provided) in these 13 intervention centres continuously for 5.5 years from 2000 until mid-2005, when the last child enrolled in the intervention group had their 3-year skin examination. The intervention generally involved children wearing study garments for a duration of at least 3 years of follow-up (from the time baseline naevus count was performed). Children leaving the daycare centre permanently before achieving 3 or more years of follow-up were given a final skin examination prior to departure, whenever possible, so that data for shorter periods of observation could also be included in the analysis (intention to treat). Staff members at intervention centres were trained to dress all children in this clothing on arrival at the centre each day in order to ensure that each child's trunk, posterior neck, upper arms and thighs were fully covered at all times when outdoors (i.e. T-shirt sleeves to cover to at least the elbows and shorts to cover to below the knees). Staff were instructed not to change children back into their own clothes until just prior to them leaving the centre at the end of each day. Laminated signs were also put on the exit doors of intervention child-care buildings to remind staff to ensure all children were dressed in study clothing before going outdoors. Compliance in intervention centres was observed and recorded when collecting dirty garments for laundering twice per week and also by monitoring weekly laundry volumes at these centres. Parents of “intervention children” were also educated about the correct fit and use of the study clothing used in the daycare setting. A UPF 50-plus legionnaire hat and high-UPF swimwear (long-sleeved UPF 40 nylon taslon shirt and commercially available UPF 50-plus Lycra (nylon elastane) suit with long sleeves with either full or knee-length legs) was given to each child attending an intervention centre to use when swimming at home or places other than daycare (issued at time of recruitment and annually thereafter for 3 years at the beginning of Summer). Home use of sun-protective garments (including the sun-protective swimwear given to intervention children) was unable to be monitored by direct observation. Consequently, this was achieved by including relevant questions in the self-administered sun exposure questionnaire completed annually by the parents of participating children for the duration of the intervention (3+ years). The 12 daycare centres assigned to the control group did not receive sun-protective clothing. Likewise the children attending the control daycare centres received no sun-protective clothing for daycare or home use, and continued to receive the usual level of sun-protection provided by the daycare centre they attended for the duration of the study. To prevent contamination of the control population, the study garments were manufactured for the study only. Similar to children in the intervention group, control children were examined for melanocytic naevi at baseline and annually thereafter for 3+ years, or until they were ready to start school or leave the centre for other reasons (relocating etc). Movement of children between intervention and control centres was monitored.