Table 2

Participant outcomes post-treatment

OutcomeILF-NF + TAU*
n = 34
TAU*
n = 33
Mean difference (95 % CI)p value
Primary outcome
 Quality of life0.54 ± 0.170.58 ± 0.16−0.04 (−0.13 to 0.04)0.28
Secondary outcomes
 Alcohol use0.13 ± 0.180.11 ± 0.180.02 (−0.07 to 0.11)0.65
 Drug use0.04 ± 0.070.04 ± 0.080.00 (−0.04 to 0.04)0.94
 Mental distress§2.08 ± 0.552.06 ± 0.640.02 (−0.27 to 0.32)0.89
 Sleep quality5.2 ± 2.75.3 ± 3.2−0.1 (−1.5 to 1.3)0.89
 Restlessness4.1 ± 2.55.9 ± 2.8−1.8 (−3.1 to −0.5)0.006
 Obsessive thinking5.7 ± 2.35.5 ± 3.00.2 (−1.1 to 1.5)0.76
 Perceived functioning**23.0 ± 9.625.8 ± 8.9−2.8 (−7.3 to 1.7)0.22
  • CI = confidence interval; EuropASI = Addiction Severity Index, European version; ILF-NF = infralow frequency neurofeedback; TAU = treatment as usual.

  • * Data are reported as mean ± standard deviation.

  • Measured using the QoL-5 scale, ranging from 0.1 to 0.9, where 0.9 is the highest or best score.

  • Measured using the EuropASI, which uses a composite score of 0 (no problem) to 1 (severe problem).

  • § Measured using the Hopkins Symptom Check List 10 (SCL-10). Responses are scored on a 4-point scale of 1 to 4 and averaged to a global severity index; a higher score indicates higher distress.

  • Measured using 10 cm visual analogue scales. The sleep quality scale ranged from “poor” to “good,” and the restlessness and obsessive thinking scales ranged from “none” to “very high.”

  • ** Measured using the Outcome Rating Scale; scores range from 0 to 40, and higher scores indicate better functioning.