CAT/C/ATG/CO/1 non-coercive investigation techniques. The State party should develop and implement specific methodologies to assess the effectiveness and impact of such training. Data collection 47. The Committee regrets the absence of comprehensive and disaggregated data on complaints, investigations, prosecutions and convictions in cases of torture and ill-treatment perpetrated by law enforcement and prison personnel, as well as violence against women and human trafficking (arts. 2, 12, 13 and 16). 48. The State party should compile statistical data relevant to the monitoring of the implementation of the Convention at the national level, including data on complaints, investigations, prosecutions and convictions in cases of torture and ill-treatment perpetrated by law enforcement and prison personnel, violence against women and human trafficking, as well as on means of redress, including compensation and rehabilitation provided to victims. Follow-up procedure 49. The Committee requests the State party to provide, by 11 August 2018, information on follow-up to the Committee’s recommendations contained in paragraphs 18, 22, 26, 28 (b), (c), (d), (e) and (f) and 38 (a), (c) and (d). In that context, the State party is invited to inform the Committee about its plans for implementing, within the coming reporting period, some or all of the remaining recommendations in the concluding observations. Other issues 50. The Committee encourages the State party to consider making the declarations under articles 21 and 22 of the Convention. 51. The Committee invites the State party to consider ratifying the Optional Protocol to the Convention as soon as possible. 52. The Committee invites the State party to consider ratifying the core United Nations human rights instruments to which it is not yet party. 53. The State party is invited to submit its common core document, in accordance with the requirements contained in the harmonized guidelines on reporting under the international human rights treaties (HRI/GEN.2/Rev.6). 54. The Committee requests the State party to disseminate widely the present concluding observations, in appropriate languages, through official websites, the media and non-governmental organizations. 55. The Committee calls upon the State party to comply with its reporting obligations under article 19 of the Convention and to submit its report, which will be considered its second, by 11 August 2021. To that end, the Committee invites the State party to agree, by 11 August 2018, to prepare its report under the simplified reporting procedure, whereby the Committee will transmit to the State party a list of issues prior to reporting. The State party’s response to that list of issues will constitute its next periodic report under article 19 of the Convention. 9