Table 2 Median values of the neurophysiological measures used in this study.

   Psychological distress(HAD total score)

11 [6–16]

10 [7–16]

12 [9–16]

12 [6–16]

0.58

   Colonic transit time(days)

1.4 [1.0–2.1]

2.1 [1.3–3.5]

1.1 [0.7–1.7]

1.5 [1.1–2.1]

<0.001

   Early rectal tone response(%)

31 [1.5–63]

33 [7.1–57]

30 [0.8–62]

26 [−2.7–63]

0.94

   Late rectal tone response(%)

36 [1.1–80]

35 [10–79]

25 [−15–75]

25 [−7.9–71]

0.57

   Rectal dynamic compliance(ml mmHg⁻¹)

5.9 [4.2–8.2]

5.9 [4.9–8.2]

6.3 [4.1–8.5]

6.2 [3.7–8.0]

0.83

   Rectal static compliance(ml mmHg⁻¹)

8.4 [6.2–10]

9.0 [6.6–10.4]

7.9 [5.9–9.6]

8.3 [6.1–10]

0.60

   Rectal first sensation threshold(mmHg)

7 [7–12]

7 [7–12]

7 [7–12]

7 [7]

0.07

   Rectal pain threshold(mmHg)

32 [27–42]

32 [26–45]

31 [22–39]

32 [27–42]

0.20

   SI phase III time(s)

477 [356–776]

412 [358–694]

659 [434–803]

414 [305–569]

0.003

   SI fasted contraction frequency(minute⁻¹)

1.4 [1.1–1.9]

1.4 [1.2–1.8]

1.7 [1.3–2.0]

1.4 [1.1–1.6]

0.06

   SI fed contraction frequency(minute⁻¹)

2.9 [2.4–3.4]

3.1 [2.6–3.4]

2.8 [2.4–3.5]

2.7 [2.3–3.5]

0.64

   SI potential difference, mean(mV)

−0.31 [−0.77–0.23]

−0.31 [−0.85–0.06]

−0.59 [−0.98–0.01]

−0.02 [−0.40–0.63]

0.01

   SI potential difference, max(mV)

−9.9 [−11–8.8]

−9.6 [−10–9.3]

−10 [−11–8.9]

−9.8 [−11–8.1]

0.70

   SI potential difference, rate of rise (mV s⁻¹)

−0.065 [−0.095–0.048]

−0.09 [−0.19–0.06]

−0.06 [−0.08–0.04]

−0.07 [−0.09–0.05]

0.06

   Baroreceptor sensitivity(ms mmHg⁻¹)

14 [10–19]

11 [8–18]

14 [10–19]

13 [11–18]

0.83

   Baroreceptor effectiveness

0.36 [0.22–0.53]

0.28 [0.22–0.50]

0.35 [0.24–0.48]

0.47 [0.19–0.57]

0.54