E/C.12/MKD/CO/2-4 54. The Committee recommends that the State party intensify its efforts to improve school enrolment and retention rates of Roma children and their academic performance, including by providing mentoring and tutoring services and other special assistance measures for Roma children. It also recommends that the State party take all measures necessary to address the overrepresentation of Roma children in special schools and special classes in mainstream schools, including a review of the classification criteria and the adoption of inclusive and integrated education programmes. D. Other recommendations 55. The Committee encourages the State party to ratify the Optional Protocol to the International Covenant on Economic, Social and Cultural Rights. 56. The Committee encourages the State party to consider ratifying the International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families and the International Convention for the Protection of All Persons from Enforced Disappearance. 57. The Committee recommends that the State party take steps to progressively develop and apply appropriate indicators on the implementation of economic, social and cultural rights in order to facilitate the assessment of progress achieved by the State party in complying with its obligations under the Covenant for various segments of the population. In this context, the Committee refers the State party to, inter alia, the conceptual and methodological framework on human rights indicators developed by the Office of the United Nations High Commissioner on Human Rights (HRI/MC/2008/3). 58. The Committee requests the State party to include in its next periodic report comparative annual statistics on the realization of each of the rights enshrined in the Covenant, disaggregated by age, sex, ethnic origin, urban and rural population and other relevant criteria. It also requests detailed information on the evolution of the State party’s revenues, disaggregated by source, and of the budgets allocated in the areas relating to the Covenant rights. 59. The Committee requests the State party to disseminate the present concluding observations widely among all levels of society at national, municipal and territorial levels, particularly among parliamentarians, public officials and judicial authorities, and to inform the Committee, in its next periodic report, about the steps taken to implement the recommendations contained herein. The Committee also encourages the State party to engage non-governmental organizations and other members of civil society in the follow-up to the present concluding observations and in the process of consultation at the national level prior to the submission of its next periodic report. 60. The Committee requests the State party to submit its fifth periodic report, to be prepared in accordance with the reporting guidelines adopted by the Committee in 2008 (E/C.12/2008/2), by 30 June 2021. The Committee also invites the State party to update its common core document in accordance with the harmonized guidelines on reporting under the international human rights treaties (see HRI/GEN/2/Rev.6, chap. I). 11