. 2021 Dec 14;9:e12330. doi: 10.7717/peerj.12330

Table 2. Characteristics of the participants and baseline outcomes.

	Experiment 1 Low conditioning stimulus (VAS 40)/ dual test stimuli	Experiment 2 High conditioning stimulus (VAS 60)/ dual test stimuli	Experiment 3 High conditioning stimulus (VAS 60)/ single test stimulus	Total	P-Value^c
Demographics	n= 29	n= 31	n= 29	N = 89
Sex, male (%)	14 (48)	17 (55)	14 (48)	45 (51)	p = .896
Age, years	24 (21–28)^a	24 (22–24)^a	22 (20–26)^a	24 (21–28)^a	p = .204
Height, cm	177 (9)	181 (10)	176 (10)	178 (10)	p = .377
Weight, kg	75 (12)	74 (12)	71 (68–79)^a	73 (65–81)^a	p = .837
BMI, kg/m²	24.0 (2.9)	22.5 (2.3)	23.5 (22.0–25.3)^a	23.1 (21.2–25.2)^a	p = .076
Sports, hours/week	5 (2.5–6.5)^a	4 (3–5)^a	4.5 (2.5–6.0)^a	4 (3–6)^a	p = .328
Anxiety, GAD-7	1 (0–2.5)^a	2 (0–3)^a	1 (0–3)^a	1 (0–3)^a	p = .377
Baseline Pressure Pain Threshold, kPa
Neck
Sequential	418 (143)	438 (159)	456 (142)^b	438 (148)	p = .632
Parallel	410 (127)	476 (183)	456 (142)^b	448 (154)	p = .242
Forearm
Sequential	407 (158)	398 (138)	456 (140)^b	420 (146)	p = .262
Parallel	395 (118)	425 (141)	456 (140)^b	425 (134)	p = .232
Lower leg
Sequential	646 (273)	680 (283)	727 (277)^b	684 (277)	p = .540
Parallel	577 (496–690)^a	705 (276)	727 (277)^b	688 (280)	p = .411
Cold Pressor Test Temperature CS (°C)	11.9 (11.7–12.0)^a	9.0 (8.8–9.3)^a	9.9 (9.4–10.7)

Notes.

Data are presented as mean (SD) unless otherwise specified.

Median (IQR).

baseline measurements in Experiment 3 are the same for both designs.

No significant differences for sociodemographic data between the three experiments or between sequential versus parallel design BMI, body mass index; GAD-7, generalised anxiety disorder seven items; PPT, Pressure Pain Threshold; kPa, kilo Pascal; CS, Conditioning Stimulus