Table 1

Comparison of characteristics of children at initial clinical assessment who were interviewed as part of the SMILE trial and PROMs study compared with children who were assessed and treated by the specialist service during the same period (2010–2012)

SMILE trialPROMs study
Study sample (n=13*) unless otherwise shownCFS cohort (n=511) unless otherwise shownp Value†Study sample (n=13) unless otherwise shownCFS cohort (n=530) unless otherwise shownp Value†
Mean (SD)Mean (SD)Mean (SD)Mean (SD)
Age (years)‡14.5 (1.5)14.0 (1.6)0.2111.3 (2.7)13.7 (1.9)<0.001
Female10 (76.9%)387 (75.7%)0.925 (38.5%)385 (72.6%)0.01
nMedian (Q1–Q3)nMedian (Q1–Q3)nMedian (Q1–Q3)nMedian (Q1–Q3)
Time to assessment (months)1212 (6–17)42112 (8–24)0.4098 (6–12)43812 (8–24)0.07
Chalder Fatigue score (0–33)1326 (23–28)47926 (22–29)0.781324 (17–25)49125 (22–28)0.07
SF-36 physical function (0–100)1350 (45–55)46955 (35–70)0.961150 (30–75)48450 (30–70)0.85
Anxiety (SCAS) (0–90)1245 (21–58)44930 (18–45)0.121016 (8–26)46529 (17–43)0.01
No. of symptoms (0–14)139 (7–10)5758 (7–10)0.52138 (7–10)5288 (6–10)0.91
Anxiety (HADS) (0–21)1312 (8–15)4759 (6–12)0.0987 (4–9)4358 (5–12)0.23
Depression (HADS) (0–21)129 (7–11)4788 (5–10)0.1087 (2–9)4387 (2–9)0.31
Visual analogue pain (0–100)1242 (29–57)46157 (24–73)0.281261 (46–81)47657 (24–73)0.24
School attendance past week
n=13

n=541

n=13

n=559
None0 (0.0%)101 (21.2%)0.244 (30.8%)104 (21.0%)0.57
10%2 (15.4%)49 (10.3%)0 (0.0%)53 (10.7%)
20%2 (15.4%)29 (6.1%)1 (7.7%)37 (7.5%)
40%1 (7.7%)88 (18.5%)0 (0.0%)88 (17.7%)
60%3 (23.1%)100 (21.0%)3 (23.1%)95 (19.2%)
80%3 (23.1%)84 (17.6%)4 (30.7%)89 (17.9%)
100%2 (15.4%)21 (4.4%)1 (7.7%)26 (5.4%)
Not applicable0 (0.0%)5 (1.1%)0 (0.0%)4 (0.8%)
  • *Characteristics included for one child whose mother was interviewed (the child was not interviewed).

  • †χ2 tests for proportions, Kruskal–Wallis test for continuous measures.

  • ‡Age for the SMILE study and the CFS cohort is age at first assessment. Age for the PROMs study is age at interview. This is because children were recruited from follow-up visits not at clinical assessment.

  • CFS, Chronic Fatigue Syndrome; HADS, Hospital Anxiety and Depression Scale; PROMs, patient-reported outcome measures; SCAS, Spence Children's Anxiety Scale; SMILE, Specialist Medical Intervention and Lightning Evaluation.