Table 3

The associations between demographic, clinical and psychosocial factors and the calculated mean daily dose reaching the face (SED) for the patients with XP

VariableDifference in mean daily UV dose to face for 1 SD change in predictor variable (SED)95% CIP value
LowerUpper
Timeline (how long will XP last?)−0.036−0.042−0.028 0
Photoprotection control: perceived level of control of UV protection over XP 0.0320.0110.056 0.004
Abnormal sensitivity to sunburn −0.058−0.096−0.015 0.008
Necessity’: perceived importance of UVR protection to health −0.034−0.058−0.009 0.008
Treatment control: perceived level of control of medical treatment over XP 0.0220.0050.04 0.012
Satisfaction with social support 0.0230.0020.044 0.028
Automaticity: degree to which avoiding going outside is automatic −0.03−0.057−0.002 0.033
Age at diagnosis 0.030.0020.059 0.036
Automaticity: degree to which photoprotection is automatic −0.033−0.0640 0.048
Illness concern: how concerned about the XP0.015−0.0010.031 0.074
Male−0.052−0.1040.005 0.075
‘Concerns’: perceived damage to health from UVR protection−0.021−0.0430.002 0.079
Understanding: perception of how well I understand XP0.012−0.0070.033 0.222
Consequences of XP on life−0.024−0.0630.016 0.241
Emotional representation: degree of emotional impact of XP−0.017−0.0460.012 0.246
Age started photoprotection0.016−0.0130.047 0.275
‘Identity’: how much patient experiences symptoms of XP−0.015−0.0420.013 0.289
Previous mucocutaneous malignancy0.03−0.0280.093 0.311
Confidence in ability to avoid going outside over next week−0.013−0.0380.013 0.32
Ethnicity (white British or non-white British)0.024−0.0260.076 0.355
Psychological well-being (SWEMWBS score)0.011−0.0130.036 0.376
Level of social support−0.01−0.0350.016 0.438
Cognitive impairment0.024−0.0650.123 0.602
Personal control: perceived level of control over XP−0.007−0.0340.02 0.605
Confidence in ability to photoprotect when out over next week0.005−0.020.03 0.704
Difference between ‘necessity’ and ‘concerns’0.003−0.0170.023 0.769
Strength of intention to avoid going outside over next week0.003−0.0250.031 0.833
Strength of intention to photoprotect when out over next week−0.002−0.0220.02 0.887
Age0.001−0.0330.036 0.956
  • This is the numerical data represented in figure 1. For clarity, the factors are presented in order of increasing p value, and those which can be seen to have an association with mean daily dose of UVR reaching the face, significant at the 5% level, are highlighted in red.

  • *Difference between the mean daily dose of UVR reaching the face (SED) for a 1 SD change in the predictor variable for continuous variables and change relative to reference group (eg, ‘males’ vs ‘females’) for categorical variables.

  • SED, standard erythemal dose; SWEMWBS, short-form Warwick-Edinburgh Mental Well-Being Scale; UVR, ultraviolet radiation; XP, xeroderma pigmentosum.