The stress management program (SM) is a program which has been tailored to meet the specific needs of low-SES participants. The SM consists of 4-weekly sessions (1.5hours/session) and a follow-up session 8 weeks later. A core element of SM is its group-based format in which psycho-educative topics on stress responses and coping and motivation to stop smoking link up with cognitive and behavioural technique activities.

The stress management + buddy program (SM-B) includes the same psycho-educative topics and exercises, cognitive and behavioural technique activities as the SM condition. The SM-B in addition to SM utilises one-to-one support through a buddy selected by a participant. A buddy, 18 year or older is a student or a volunteer who is recruited and trained by Indigo Rijnmond. The buddy pairs up with a participant and provides the following: supports participant in managing and filling in tax/welfare papers; 2) helps a participant to get a grip over his/her personal finances; and 3) helps a participant to overcome daily barriers (eg. arranging childcare). Over the duration of the course, the buddy meets up 6 times with a participant every second week in a public area.

Participants in the control condition are instructed to continue with their normal daily behaviour. They will be invited to complete the questionnaires and objective measurements at the equivalent times as the intervention groups, thus at baseline, 4 weeks after baseline and 12 weeks after baseline. After the control period, participants in the control condition will be offered the intervention.

Participants follow the SM program.

Change in self-reported Stress.

The Depression, Anxiety and Stress (DASS) questionnaire will be used to measure change in self-reported stress from baseline (T0), at 4 weeks after baseline (T1) and at 12 weeks after baseline (T2).

The DASS is a 21-item questionnaire with three self-report scales (Depression, Anxiety and Stress). Scores for depression, anxiety and stress are determined by summing the scores of the 21 items. Ranges for depression, anxiety and stress are 0-28, 0-20, and 0-33, respectively. Lower scores indicate less severity.

In this study participants will be asked to complete the DASS-21 questionnaire at three different time points (T0, T1 and T2). This is done so the investigators can assess the change in scores of self-reported stress across time points (T0, T1 and T2).

Change in objective evaluations of stress based on heart rate variability (HRV) from baseline (T0), at 4 weeks after baseline (T1) and at 12 weeks after baseline (T2).

HRV indicates variability of time intervals between two consecutive heartbeats with each heartbeat having a R-wave which peaks in the R peak. The variations between two RR intervals are defined as HRV. A higher HRV value reflects a greater variation of the RR whereas a lower HRV indicates small variation.

Participants beat-to-beat heart rate is measured using wrist wearables provided by Philips. During the measurements, the wearables are mounted on a participant's wrist and the participant is instructed to sit in a resting state for five minutes while the beat-to-beat heart rate is recorded. HRV analysis is derived from the recorded data using an appropriate software program. To assess change over time points (T0, T1 and T2), participants's beat-to-beat heart rate will be measured at three time points

Change in self-reported Smoking.

The Global Adult Tobacco Survey (GATS) questionnaire will be used to measure change in self-reported smoking from baseline (T0), at 4 weeks after baseline (T1) and at 12 weeks after baseline (T2).

Participants will be asked to complete the questionnaire at three time points (T0, T1 and T2). This is done so the investigators can assess the change in self-reported smoking across time points.