A Randomised Controlled Trial of the Efficacy of Triple P (Positive Parenting Program) Seminar Series as a Universal Parenting Intervention for the Prevention of Emotional and Behavioural Difficulties in Greek Children Aged 2 to 12.

Phase 1: Recruitment Child and family organisations will invite the general public by advertising the study through the organisations' member lists, contacts with schools and other health institutions, social networks, and mass media. Parents who have at least a child between 2 to 12 years old, living in the general area of Attica and being available to attend three Seminars (once per month) will be eligible. The researcher will receive from the organisations the list of all parents who contacted them and were interested in taking part in the study; the list will then be shared with his assistant. The assistant will sign a subcontract. All parents will receive an envelope which includes: (1) a thank you letter; (2) participant information sheet and two informed consents; (3) the pre-assessment baseline booklet including background information, parenting and child measures; (4) a pre-paid envelope so they could easily return them.

Written-informed consent: Eligible adult participants will provide informed consent. The adult informed consent process involves presenting a detailed written description of the study as it is described on the printed information and consent forms. Participants will be informed of the procedures for ensuring their protection, including:

1. participation is voluntary and free of charge;
2. participants will be informed that they will have an equal chance to get the Seminar Series through a fair process;
3. participants will be informed that their personal contact details will be shared with the researcher and his assistant;
4. the questionnaires which will be distributed are not anonymous. This is because all questionnaires will be distributed by mail;
5. the confidentiality of participants' personal data will be guaranteed though specific procedures to protect their anonymity: (a) all information provided will remain strictly confidential; (b) participants' names and other identifiers will not be written on any transcriptions or other research data; (c) unique non-personally identifying ID numbers instead of names on research materials will be used. This code will be placed on the survey and other collected data. Through an identification key, the researcher's assistant will be able to link records to participants' identity; and (d) data will maintained in locked computer databases, and participants study files, video and audio tapes of the Seminars in locked filing cabinets in locked rooms; (e) only the researcher, his assistant and the researcher's supervisor will have access to the data; (f) at the end of the project all information, including the video and audio tapes of the first 3 Seminars will be in locked cabinets at the researcher's office and all databases, audio and video files will be stored to his computer for future academic research and/or training of other health professionals; a password will be required for access to the databases. After focus group transcription the video and audio tapes of focus groups will be destroyed by the researcher;
6. participants will be informed that the Seminar Series will be audio and video recorded and the tapes will only be used for academic and training reasons. At Seminar 1, 2, 3 the cameras will be set at the back of the room, behind the participants so that their face will not be recorded. For focus groups video will only be used if the sound of the audio recorder is unclear to distinguish what it is said, as parents may speak simultaneously or soft. After focus group transcription the video and audio tapes will be destroyed by the researcher.
7. participants can refuse to participate in either the intervention or research and/or can discontinue participation without penalty at any time by advising the researchers of this decision. By withdrawing from the study, they also have the right to withdraw all their data collected until that point.
8. in case of further questions participants can directly ask the researcher by phone or email who will do his best to answer their query. If they remain unhappy and wish to make a formal complaint, they can contact the Research Ethics Committee at the University of Oxford (ethics@socsci.ox.ac.uk; +44 (0)1865 614871; Social Sciences & Humanities Inter-Divisional Research Ethics Committee, Oxford University, Hayes House, 75 George Street, Oxford, OX1 2BQ, UK).

For parents who request additional professional help, a list with psychological health services will be provided. Participants may participate only after having read the information sheet and had signed it. All consenting and assenting participants will be offered a copy of the informed consent form. Parents who do not respond to their invitation for the Seminars will be asked to give phone-consent.

Regarding the consent form, the information sheet and the rest of the questionnaires which were in English, first they were translated by the researcher into Greek. All translations were reviewed by two Greek parents and a Greek Lecturer in Linguistics at University of Cambridge for understanding and relevance of the translated terms. All translations were adjusted according to the reviewers' comments. At the end, a Greek-American Health Professional checked if the final Greek translations matched the original English ones. The Conners and the SQD have officially been translated in Greek.