Table 4 Predictors of MDMA-related harm experience

Age

 18–21 vs. 36+

1.87 (0.81–4.29)

2.38 (0.91–6.22)

0.98 (0.52–1.83)

 22–25 vs. 36+

2.22 (0.96–5.15)^a

2.49 (0.94–6.58)

0.94 (0.49–1.80)

 26–29 vs. 36+

1.38 (0.55–3.50)

1.51 (0.53–4.33)

0.99 (0.49–1.99)

 30–35 vs. 36+

0.88 (0.88–2.54)

1.06 (0.32–3.49)

0.80 (0.37–1.73)

Female gender

1.21 (0.82–1.79)

1.01 (0.71–1.42)

Māori ethnicity

0.84 (0.48–1.48)

1.03 (0.64–1.66)

Student

1.13 (0.78–1.64)

0.90 (0.64–1.26)

Region of residence

(ref = Otago)

 Auckland

1.08 (0.61–1.89)

1.26 (0.76–2.09)

 Wellington

1.13 (0.62–2.07)

1.48 (0.87–2.51)

 Canterbury

1.11 (0.65–1.88)

1.27 (0.79–2.06)

 Other

1.23 (0.71–2.16)

1.37 (0.82–2.28)

Frequency of MDMA use

(ref = once a year or less often)

 Weekly or more often

6.92 (3.1-15.46)***

5.05 (1.93–13.24)*

2.74 (1.01–7.42)*

1.31 (0.42–4.04)

 Fortnightly

1.71 (0.73–3.99

0.73 (0.25–2.11)

4.94 (2.15–11.35)***

3.25 (1.25–8.44)*

 Monthly

1.54 (0.76–3.13

0.87 (0.38-2.00)

4.44 (2.13–9.28)***

3.17 (1.40–7.15)**

 Every 2–3 months

1.38 (0.72–2.68)

0.75 (0.35–1.63)

3.49 (1.72–7.10)***

2.56 (1.17–5.60)*

 Every 4–6 months

1.22 (0.62–2.42)

0.84 (0.39–1.82)

2.46 (1.18–5.14)*

1.95 (0.88–4.33)

Average dose per session

(ref = 100 mg)

 < 50 mg

0.33 (0.10–1.06)^a

0.28 (0.08-1.00)

0.78 (0.26–2.32)

1.65 (0.52–5.25)

 51-99 mg

0.84 (0.35–1.99)

0.84 (0.33–2.16)

1.28 (0.50–3.28)

1.60 (0.58–4.42)

 101-150 mg

0.51 (0.22–1.16)

0.39 (0.16–0.96)*

1.57 (0.69–3.58)

1.65 (0.68–4.01)

 151-250 mg

0.97 (0.48–1.96)

0.66 (0.30–1.46)

2.37 (1.10–5.11)*

2.15 (0.94–4.94)

 251-500 mg

0.95 (0.45–2.01)

0.57 (0.24–1.39)

3.24 (1.48–7.10)**

2.89 (1.22–6.87)*

 > 500 mg

1.79 (0.76–4.21)

0.68 (0.23–2.04)

1.36 (0.49–3.79)

1.19 (0.38–3.78)

 “I don’t know”

0.80 (0.37–1.72)

0.81 (0.35–1.89)

1.30 (0.56–3.01)

2.16 (0.86–5.39)

Self-reported harm reduction knowledge (ref = know nothing)

 Know little

0.91 (0.43–1.91)

2.01 (0.81–4.50)

1.97 (0.75–5.18)

 Know moderate amount

0.88 (0.43–1.77)

2.31 (0.96–5.55)^a

1.91 (0.74–4.93)

 Know large amount

0.68 (0.32–1.46)

3.07 (1.25–7.53)*

2.47 (0.92–6.60)

MDMA harm

-

-

5.57 (3.73–8.32)***

6.38 (4.06–10.03)***

Non-MDMA harm

5.57 (3.73–8.32)***

6.29 (3.99–9.92)***

-

-

Use of KYSNZ

1.95 (1.32–2.89)***

2.50 (1.56–3.99)***

1.92 (1.35–2.74)***

1.13 (0.74–1.73)

Use of colorimetric reagent test

1.28 (0.88–1.86)

2.15 (1.53–3.03)***

1.60 (1.06–2.41)*

Meets dependence threshold

6.34 (3.67–10.97)***

5.22 (2.70–3.99)***

1.64 (0.90–2.99)

Constant

0.05***

0.01***

Hosmer and Lemeshow Goodness-of-fit

0.359

0.744