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Bulletin of the World Health Organization logoLink to Bulletin of the World Health Organization
. 2019 Apr 4;97(6):394–404C. doi: 10.2471/BLT.18.222448

Comparison of essential medicines lists in 137 countries

Comparaison des listes des médicaments essentiels de 137 pays

Comparación de las listas de medicamentos esenciales en 137 países

مقارنة قوائم الأدوية الأساسية في 137 بلداً

137 国的基本药物清单比较

Сравнение перечней основных лекарственных средств в 137 странах

Nav Persaud a,, Maggie Jiang a, Roha Shaikh a, Anjli Bali a, Efosa Oronsaye a, Hannah Woods a, Gregory Drozdzal a, Yathavan Rajakulasingam a, Darshanand Maraj a, Sapna Wadhawan a, Norman Umali a, Ri Wang a, Marcy McCall b, Jeffrey K Aronson b, Annette Plüddemann b, Lorenzo Moja c, Nicola Magrini c, Carl Heneghan b
PMCID: PMC6560372  PMID: 31210677

Abstract

Objective

To compare the medicines included in national essential medicines lists with the World Health Organization’s (WHO’s) Model list of essential medicines, and assess the extent to which countries’ characteristics, such as WHO region, size and health care expenditure, account for the differences.

Methods

We searched the WHO’s Essential Medicines and Health Products Information Portal for national essential medicines lists. We compared each national list of essential medicines with both the 2017 WHO model list and other national lists. We used linear regression to determine whether differences were dependent on WHO Region, population size, life expectancy, infant mortality, gross domestic product and health-care expenditure.

Findings

We identified 137 national lists of essential medicines that collectively included 2068 unique medicines. Each national list contained between 44 and 983 medicines (median 310: interquartile range, IQR: 269 to 422). The number of differences between each country’s essential medicines list and WHO’s model list ranged from 93 to 815 (median: 296; IQR: 265 to 381). Linear regression showed that only WHO region and health-care expenditure were significantly associated with the number of differences (adjusted R2: 0.33; P < 0.05). Most medicines (1248; 60%) were listed by no more than 10% (14) of countries.

Conclusion

The substantial differences between national lists of essential medicines are only partly explained by differences in country characteristics and thus may not be related to different priority needs. This information helps to identify opportunities to improve essential medicines lists.

Introduction

More than 5 billion people live in countries that use essential medicines lists. These lists typically contain hundreds of medicines intended to meet the priority health-care needs of a population.13 Since the World Health Organization (WHO) published the first Model list of essential medicines in 1977, the list has been revised every two years and adapted to circumstances in more than one hundred countries. Governments and health-care institutions use essential medicines lists to determine which medicines to fund, stock, prescribe and dispense.4 As essential medicines lists influence the medicines that people have access to, contents of these lists constitute important determinants of health worldwide.

Countries must select medicines for their essential lists appropriately to facilitate sustainable, equitable access to medicines and promote their appropriate use.4 Since a country’s list is intended to meet the needs of its population, countries that are geographically close or similar to each other in population size, health-care expenditure and health status might be expected to have similar essential medicines lists. Differences between such lists that are not explained by differences in country-specific needs may represent opportunities for improving the lists.

Here we aimed to compare the medicines included in national essential medicines lists with the 2017 WHO’s Model list of essential medicines,5 and to determine whether characteristics, such as WHO Region, population size, and health-care expenditure account for the differences.

Methods

We prespecified the main analysis for this observational study before data collection (NCT03218189) and report the results using the STROBE reporting guidelines.6,7

In June 2017, we searched the WHO essential medicines and health products information portal. This online repository contains hundreds of publications on medicines and health products related to WHO priorities and has a full section dedicated to national lists of essential medicines.2,3 A WHO information specialist actively searched for updated versions of national lists, including national formularies, reimbursement lists and lists based on standard treatment guidelines. We included all national lists of essential medicines that were posted on the repository irrespective of publication date and language. When we found more than one national list from the same country, we used the most recent list.

We excluded documents that were not essential medicines lists, such as prescribing guidelines. We also excluded diagnostic agents, antiseptics, disinfectants and saline solutions.

Data collection processes

We developed a data extraction method for medicines in national lists, which we pilot-tested on lists from five countries. One of six reviewers extracted information from each country and another reviewer verified the information before inclusion in an electronic database.

For identified countries with essential medicines lists, we collected eight country characteristics that might explain differences in the lists and that are widely available and commonly used in international comparisons: WHO region; population size; life expectancy; infant mortality; gross domestic product (GDP) per capita; health care-expenditure per capita; GINI index as a measure of income inequality; and the corruption perception index. In June 2017, we extracted data on WHO Region and per capita health-care expenditure from the WHO Global Health Observatory, the most recent information available at the time.8 We extracted data on population, life expectancy, infant mortality and GDP per capita from the Central Intelligence Agency’s World Factbook.9 We obtained the GINI index from the most recent data available from the World Bank in the United Nations Human Development Report 2016.10 We retrieved the corruption perception score from Transparency International’s 2016 corruption perceptions index.11

Data extraction

From each country’s list we abstracted medicines using International Nonproprietary Names (INNs).12 For medicines whose names were not in English, we used the Anatomical Therapeutic Chemical classification system,13 if available, or translated the names using Google Translate.14 We listed each medicine individually, whether it was part of a combination product or not. We treated medicine bases and their salts (e.g. promethazine hydrochloride and promethazine) as the same medicines, as well as different compounds of the same vitamin or mineral (e.g. ferrous fumarate and ferrous sulfate).

We used the Anatomical Therapeutic Chemical code for each medicine and the Anatomical Therapeutic Chemical structure to determine the level of relatedness between medicines: level 1, anatomical main group (e.g. metformin is “A” for alimentary tract); level 2, therapeutic subgroup (e.g. metformin is “A10” for alimentary tract medicines used to treat diabetes); level 3, pharmacological subgroup (e.g. metformin is “A10B” for alimentary tract medicines used to treat diabetes that lower blood glucose); level 4, chemical subgroup (e.g. metformin is “A10BA” for alimentary tract medicines used to treat diabetes that lower blood glucose that are biguanides).15 WHO’s model list indicates (with a square box) that some listed medicines are merely exemplars of several medicines that should be considered therapeutically equivalent.5 We assumed that the medicines in the same chemical subgroup as the exemplar were equivalent (e.g. enalapril is equivalent to all other in the chemical subgroup C09A: captopril, lisinopril, perindopril, ramipril, quinapril, benazepril, cilazapril, fosinopril, trandolapril, spirapril, delapril, moexipril, temocapril, zofenopril and imidapril), except when WHO’s list specified particular equivalent medicines (e.g. bisoprolol is specified as equivalent to atenolol, metoprolol, and carvedilol). As a result of uncertainty whether these medicines are truly equivalent, and because we do not know how countries interpreted the indications of equivalence, or if they used them at all, we also report results disregarding the equivalence to exemplars.

Data analysis

For descriptive data, we calculated medians with interquartile ranges (IQRs).

Comparison with WHO’s model list

To determine whether countries’ characteristics accounted for differences between each country’s list and the 2017 WHO model list, we created a linear regression model with the total number of differences from the WHO’s model list as the dependent variable and the following characteristics as independent variables: WHO region, population size, life expectancy, infant mortality, GDP per capita, and health-care expenditure per capita. We had to exclude the variables inequality and corruption perception, since only 95 (69 %) countries had available information. We present the adjusted R2 values for the number of independent variables. We conducted several post-hoc sensitivity analyses: removed longer lists to assess the effect of outliers, employed the Tanimoto coefficient that accounts for list length and used the 2015 WHO model list instead of the 2017 list as a reference to allow for a delay in updating national lists.16 We used R statistical package (R Foundation, Vienna, Austria).

Country comparisons

To calculate a similarity score, we divided medicines into those that are commonly listed (by at least 50% of countries) and those that are uncommonly listed (by less than 50% of countries). For each country’s list we calculated the score by counting the medicines on that list that are commonly listed and subtracting the number of uncommonly listed medicines. This calculation provides a similarity integer score for each country; positive scores indicate that most medicines in the country’s list are commonly listed in other countries’ lists, and negative scores indicate that most medicines are uncommonly listed in other countries’ lists.

Data sharing

The underlying data used in this study are publicly available and, separately, a database with updated information about national essential medicines lists will be maintained online.17,18

Results

We identified essential medicines lists posted on the WHO repository for 137 countries (70% of 195 countries). The total number of medicines on each country’s list ranged from 44 to 983 (median: 310; IQR: 269 to 422). In total we identified 2068 unique medicines. Table 1 (available at: http://www.who.int/bulletin/volumes/97/6/18-222448) presents the characteristics of the included countries.

Table 1. National lists of essential medicines in 137 countries.

Country GDP per capita in 2017, Intl $ Health expenditure per capita in 2014, Intl $ Year of list Total no. of medicines on list Similarity with WHO Model List, no. (%)a Dissimilarity with WHO Model List, no.b Similarity score
Afghanistan 2 000 167 2014 258 196 (78) 62 104
Albania 12 500 615 2011 214 121 (57) 93 26
Algeria 15 200 932 2016 445 161 (36) 284 −145
Angola 6 800 239 2008 64 51 (80) 13 40
Antigua and Barbuda 26 400 1208 2007 292 208 (71) 84 140
Argentina 20 900 1137 2011 468 285 (61) 183 0
Armenia 9 500 362 2010 267 234 (88) 33 129
Bahrain 49 000 2273 2015 550 271 (49) 279 −106
Bangladesh 4 200 88 2008 187 170 (91) 17 129
Barbados 18 600 1014 2011 625 266 (43) 359 −159
Belarus 18 900 1031 2012 371 192 (52) 179 −53
Belize 8 300 489 2008 370 253 (68) 117 78
Bhutan 9 000 281 2016 291 202 (69) 89 89
Bolivia (Plurinational State of) 7 600 427 2011 352 248 (70) 104 92
Bosnia and Herzegovina 12 800 957 2009 181 107 (59) 74 29
Botswana 17 000 871 2012 340 233 (69) 107 108
Brazil 15 600 1318 2014 405 235 (58) 170 −49
Bulgaria 21 800 1399 2011 361 114 (32) 247 −171
Burkina Faso 1 900 82 2014 274 217 (79) 57 124
Burundi 700 58 2012 293 204 (70) 89 97
Cabo Verde 7 000 310 2009 564 295 (52) 269 −78
Cambodia 4 000 183 2003 44 35 (80) 9 30
Cameroon 3 700 122 2010 351 247 (70) 104 83
Central African Republic 700 25 2009 295 215 (73) 80 109
Chad 2 300 79 2007 240 186 (78) 53 128
Chile 24 600 1749 2005 349 225 (64) 124 67
China 16 700 731 2012 289 178 (62) 112 43
Colombia 14 400 962 2011 370 248 (86) 122 48
Congo 6 800 323 2013 300 221 (74) 79 108
Cook Islands 16 700 486 2007 240 167 (70) 73 110
Costa Rica 16 900 1389 2014 388 225 (58) 163 4
Côte d’Ivoire 3 900 187 2014 502 266 (53) 236 −70
Croatia 24 700 1652 2010 599 286 (48) 313 −151
Cuba 12 300 2475 2012 506 282 (56) 225 −42
Czechia 35 500 2146 2012 802 264 (33) 538 −398
Democratic People's Republic of Korea 1 700 2060 2012 220 166 (75) 54 96
Democratic Republic of the Congo 800 32 2010 313 230 (74) 83 103
Djibouti 3 600 338 2007 199 150 (75) 49 105
Dominica 11 000 587 2007 284 202 (71) 82 136
Dominican Republic 17 000 580 2015 355 297 (84) 58 105
Ecuador 11 500 1040 2013 369 270 (73) 99 35
Egypt 12 700 594 2012 323 263 (81) 60 97
El Salvador 8 000 565 2009 360 253 (70) 107 82
Eritrea 1 600 51 2010 335 248 (74) 87 107
Estonia 31 700 1668 2012 405 156 (39) 249 −141
Ethiopia 2 200 73 2014 707 319 (45) 388 −209
Fiji 9 800 364 2015 296 215 (73) 81 114
Gambia 2 600 118 2001 164 126 (77) 38 92
Georgia 10 700 628 2007 247 206 (83) 41 139
Ghana 4 700 145 2010 302 219 (73) 83 104
Grenada 15 100 728 2007 282 197 (70) 85 130
Guinea 2 200 68 2012 238 194 (82) 44 116
Guyana 8 100 379 2010 280 216 (77) 64 116
Haiti 1 800 131 2012 197 182 (92) 15 153
Honduras 5 600 400 2009 365 227 (62) 138 25
India 7 200 267 2015 367 239 (65) 128 45
Indonesia 12 400 299 2011 275 222 (81) 53 127
Iran (Islamic Republic of) 20 100 1082 2014 886 342 (39) 544 −390
Iraq 16 700 667 2010 573 260 (45) 313 −143
Jamaica 9 200 476 2012 457 265 (58) 192 7
Jordan 9 200 798 2011 590 287 (49) 303 −138
Kenya 3 500 169 2016 416 310 (75) 106 30
Kiribati 2 000 184 2009 216 173 (80) 43 144
Kyrgyzstan 3 700 215 2009 316 206 (65) 110 56
Latvia 27 700 940 2012 304 127 (42) 177 −96
Lebanon 19 600 987 2014 284 232 (82) 52 108
Lesotho 3 300 276 2005 195 148 (76) 47 107
Liberia 1 300 98 2011 215 182 (85) 33 137
Lithuania 32 400 1718 2012 339 153 (45) 186 −77
Madagascar 1 600 44 2008 250 170 (68) 80 100
Malawi 1 200 93 2015 322 249 (77) 73 116
Malaysia 29 100 1040 2014 308 220 (71) 88 98
Maldives 19 200 1996 2011 535 243 (45) 292 −111
Mali 2 200 108 2012 285 220 (77) 65 127
Malta 41 900 3072 2008 607 245 (40) 362 −201
Marshall Islands 3 600 680 2007 214 142 (66) 72 80
Mauritania 4 500 148 2008 215 168 (78) 47 123
Mexico 19 900 1122 2011 706 294 (42) 412 −260
Mongolia 13 000 565 2009 256 216 (84) 41 126
Montenegro 17 800 888 2011 452 262 (58) 190 −26
Morocco 8 600 447 2012 344 252 (73) 92 78
Mozambique 1 300 79 2016 259 232 (90) 27 133
Myanmar 6 300 103 2010 315 249 (79) 67 137
Namibia 11 200 869 2016 382 262 (69) 120 72
Nauru 12 300 512 2010 230 177 (77) 53 132
Nepal 2 700 137 2011 300 242 (81) 58 116
Nicaragua 5 900 445 2011 271 212 (78) 59 125
Nigeria 5 900 217 2010 305 224 (73) 81 101
Niue 5 800 887 2006 213 141 (66) 72 75
North Macedonia 14 900 851 2008 390 218 (56) 172 −30
Oman 46 000 1442 2009 576 299 (52) 277 −94
Pakistan 5 400 129 2016 373 347 (93) 26 79
Palau 14 700 1429 2006 268 167 (62) 101 70
Papua New Guinea 3 700 109 2012 270 223 (83) 47 132
Paraguay 12 800 873 2009 306 224 (73) 82 92
Peru 13 500 656 2012 424 298 (70) 126 40
Philippines 8 400 329 2008 519 291 (56) 228 −45
Poland 29 600 1570 2017 441 177 (40) 264 −179
Portugal 30 500 2690 2011 905 256 (28) 649 −497
Republic of Moldova 6 700 514 2011 476 329 (69) 147 4
Romania 24 600 1079 2012 635 231 (36) 404 −283
Russian Federation 27 900 1836 2014 518 260 (50) 258 −118
Rwanda 2 100 125 2010 284 216 (76) 68 128
Saint Kitts and Nevis 28 200 1152 2007 290 204 (70) 86 140
Saint Lucia 14 400 698 2007 290 204 (70) 86 140
Saint Vincent and the Grenadines 11 500 917 2010 267 216 (81) 51 151
Senegal 3 500 107 2013 333 213 (64) 120 43
Serbia 15 100 1312 2010 472 237 (50) 235 −72
Seychelles 29 300 844 2010 294 210 (71) 84 114
Slovakia 33 100 2179 2012 983 291 (30) 692 −553
Slovenia 34 500 2698 2017 787 305 (39) 482 −359
Solomon Islands 2 200 108 2017 257 194 (75) 63 115
Somalia 1 064c 11 2006 82 73 (89) 9 66
South Africa 13 600 1148 2014 192 157 (82) 35 90
Sri Lanka 12 900 369 2013 318 230 (72) 88 62
Sudan 4 300 282 2014 300 175 (58) 125 34
Suriname 14 900 979 2014 285 220 (77) 65 113
Sweden 51 200 5219 2016 289 143 (49) 146 −61
Syrian Arab Republic 2 900 376 2008 964 312 (32) 652 −490
Tajikistan 3 200 185 2009 272 227 (83) 45 132
Thailand 17 900 600 2013 547 303 (55) 244 −67
Timor-Leste 6 000 102 2015 239 203 (85) 36 147
Togo 1 700 76 2012 295 234 (79) 61 109
Tonga 5 900 270 2007 229 164 (72) 65 123
Trinidad and Tobago 31 300 1816 2010 493 265 (54) 228 −41
Tunisia 11 900 785 2012 719 265 (54) 454 −283
Tuvalu 3 800 585 2010 177 150 (85) 27 139
Uganda 2 400 133 2012 363 247 (68) 116 71
Ukraine 8 800 584 2009 278 225 (81) 53 104
United Republic of Tanzania 3 200 137 2013 357 251 (70) 106 75
Uruguay 22 400 1792 2011 518 244 (47) 274 −106
Vanuatu 2 700 150 2006 177 147 (83) 30 131
Venezuela (Bolivarian Republic of) 12 500 923 2004 306 215 (70) 91 84
Viet Nam 6 900 390 2008 743 282 (38) 459 −289
Yemen 2 500 202 2009 247 201 (81) 46 131
Zambia 4 000 195 2013 286 217 (76) 69 92
Zimbabwe 2 300 115 2011 346 248 (72) 98 98

GDP: gross domestic product; Intl $: international dollars; WHO: World Health Organization.

a Number of medicines on both WHO’s model list and the national list.

b Number of medicines not on WHO’s model list.

c Estimated GDP.

Note: WHO’s model list refers to WHO’s Model list of essential medicines.

Fig. 1 shows the relationship between the number of essential medicines listed by each country and GDP. Most countries with a lower GDP had shorter national lists of essential medicines, but there were many exceptions. Sweden has a high GDP and relatively short list while Syrian Arab Republic has a low GDP and a relatively long list. Medicines in each country’s list can be found in a data repository.17,18

Fig. 1.

The number of essential medicines on national list of essential medicines in relation to countries’ gross domestic product, 2017

GDP: gross domestic product; Intl $: international dollars.

Note: We obtained the countries’ three letter codes from the International Organization for Standardization (ISO) 3166–1 Online Browsing Platform; AGO: Angola; ALB: Albania; ARG: Argentina; ARM: Armenia; ATG: Antigua and Barbuda; BDI: Burundi; BGD: Bangladesh; BGR: Bulgaria; BHR: Bahrain; BIH: Bosnia and Herzegovina; BLR: Belarus; BLZ: Belize; BRA: Brazil; BRB: Barbados; BWA: Botswana; CHL: Chile; CHN: China; CIV: Côte d'Ivoire; CMR: Cameroon; COD: Democratic Republic of Congo; COG: Congo; COK: Cook Islands; COL: Colombia; CPV: Cabo Verde; CRI: Costa Rica; CUB: Cuba; CZE: Czechia; DMA: Dominica; DZA: Algeria; ECU: Ecuador; EGY: Egypt; ERI: Eritrea; EST: Estonia; ETH: Ethiopia; FJI: Fiji; GEO: Georgia; GHA: Ghana; GUY: Guyana; HRV: Croatia; HTI: Haiti; IND: India; IRN: Islamic Republic of Iran; IRQ: Iraq; JAM: Jamaica; JOR: Jordan; KEN: Kenya; KHM: Cambodia; KNA: Saint Kitts and Nevis; LBN: Lebanon; LBR: Liberia; LCA: Saint Lucia; LTU: Lithuania; LVA: Latvia; MAR: Morocco; MDA: Republic of Moldova; MDV: Maldives; MEX: Mexico; MKD: North Macedonia; MLT: Malta; MMR: Myanmar; MNE: Montenegro; MOZ: Mozambique; MRT: Mauritania; MWI: Malawi; MYS: Malaysia; NAM: Namibia; NIC: Nicaragua; NIU: Niue; NPL: Nepal; OMN: Oman; PAK: Pakistan; PER: Peru; PHL: Philippines; PLW: Palau; POL: Poland; PRT: Portugal; ROU: Romania; SOM: Somalia; SVK: Slovakia; SVN: Slovenia; SWE: Sweden; SYC: Seychelles; SYR: Syrian Arab Republic; THA: Thailand; TTO: Trinidad and Tobago; TUN: Tunisia; TUV: Tuvalu; UGA: Uganda; URY: Uruguay; VNM: Viet Nam; VUT: Vanuatu; ZAF: South Africa. Not all country codes are shown to make this figure more readable; data for all countries are provided in Table 1.

Fig. 1

Comparison with WHO’s model list

Of the 414 eligible medicines on WHO’s model list, 73 (18%) medicines were listed by only 27 (20%) or fewer countries and 23 (6%) medicines were listed by 7 (5%) or fewer countries. Medicines recently added to WHO’s model list were generally listed by fewer countries than those medicines added earlier (available from a data repository).19 Only velpatasvir, a Hepatitis C treatment, which was added to the 2017 WHO model list , was not listed by any country. No country included all medicines on WHO’s model list; eight countries included over 300 WHO essential medicines on their list (Ethiopia, Iran [Islamic Republic of], Kenya, Pakistan, Republic of Moldova, Slovakia, Syrian Arab Republic and Thailand). Of these, Kenya, Pakistan and the Republic of Moldova listed WHO essential medicines without adding many (less than 150) other medicines. Portugal, Slovakia and Syrian Arab Republic added more than 600 medicines to their list that were not on WHO’s model list; while Angola, Bosnia and Herzegovina, Bulgaria, Cambodia and Somalia omitted more than 300 WHO essential medicines.

The numbers of differences between each country’s list and WHO’s model list ranged from 85 to 533 (median: 252; IQR: 227 to 303) or, when equivalence to exemplars was disregarded, from 93 to 815 differences (median: 296; IQR: 265 to 381). There were differences across therapeutic areas and for both communicable and noncommunicable diseases (available from a data repository).19 Fig. 2 and Fig. 3 show the relationship between countries’ health-care expenditure and essential medicines. Countries with lower health-care expenditures appear to have omitted more medicines from their lists that are on WHO’s model list (e.g. Angola and Cambodia), and countries with higher health-care expenditures appear to have included more medicines on their lists that are not on WHO’s model list (e.g. Portugal and Slovakia), although exceptions exist (e.g. Sweden).

Fig. 2.

Health expenditure and dissimilarities between national lists of essential medicines and the 2017 WHO Model list of essential medicines

WHO: World Health Organization.

Notes: The size of the circles represents the country’s health-care expenditure. We obtained the countries’ three letter codes from the International Organization for Standardization (ISO) 3166–1 Online Browsing Platform; AGO: Angola; ALB: Albania; ARG: Argentina; ARM: Armenia; BGD: Bangladesh; BGR: Bulgaria; BIH: Bosnia and Herzegovina; BLR: Belarus; BRA: Brazil; BRB: Barbados; COL: Colombia; CUB: Cuba; CZE: Czechia; DOM: Dominican Republic; DZA: Algeria; ECU: Ecuador; EGY: Egypt; EST: Estonia; ETH: Ethiopia; GMB: Gambia; HRV: Croatia; HTI: Haiti; IRN: Islamic Republic of Iran; IRQ: Iraq; KEN: Kenya; KGZ: Kyrgyzstan; KHM: Cambodia; LBR: Liberia; LTU: Lithuania; LVA: Latvia; MDA: Republic of Moldova; MDV: Maldives; MEX: Mexico; MHL: Marshall Islands; MKD: North Macedonia; MLT: Malta; MNE: Montenegro; MOZ: Mozambique; NAM: Namibia; NIU: Niue; OMN: Oman; PAK: Pakistan; PER: Peru; PLW: Palau; POL: Poland; PRT: Portugal; ROU: Romania; SDN: Sudan; SOM: Somalia; SRB: Serbia; SVK: Slovakia; SVN: Slovenia; SWE: Sweden; SYR: Syrian Arab Republic; THA: Thailand; TLS: Timor-Leste; TUN: Tunisia; TUV: Tuvalu; URY: Uruguay; VNM: Viet Nam; VUT: Vanuatu. Not all country codes are shown to make this figure more readable; data for all countries are provided in Table 1.

Fig. 2

Fig. 3.

Health expenditure and similarities between national lists of essential medicines and the 2017 WHO Model list of essential medicines

Notes: The size of the circles represents the country’s health-care expenditure. We obtained the countries’ three letter codes from the International Organization for Standardization (ISO) 3166–1 Online Browsing Platform; AGO: Angola; ARG: Argentina; ATG: Antigua and Barbuda; BFA: Burkina Faso; BGD: Bangladesh; BGR: Bulgaria; BHR: Bahrain; BRA: Brazil; BRB: Barbados; BWA: Botswana; CHL: Chile; CIV: Côte d'Ivoire; COL: Colombia; CRI: Costa Rica; CUB: Cuba; CZE: Czechia; DZA: Algeria; EST: Estonia; ETH: Ethiopia; GEO: Georgia; GMB: Gambia; HRV: Croatia; HTI: Haiti; IRN: Islamic Republic of Iran; IRQ: Iraq; JOR: Jordan; KEN: Kenya; KGZ: Kyrgyzstan; KHM: Cambodia; LTU: Lithuania; LVA: Latvia; MDA: Republic of Moldova; MDG: Madagascar; MDV: Maldives; MEX: Mexico; MKD: North Macedonia; MLT: Malta; MNE: Montenegro; MNG: Mongolia; MOZ: Mozambique; NIC: Nicaragua; OMN: Oman; PER: Peru; PHL: Philippines; POL: Poland; PRT: Portugal; ROU: Romania; SDN: Sudan; SOM: Somalia; SVK: Slovakia; SVN: Slovenia; SWE: Sweden; SYR: Syrian Arab Republic; THA: Thailand; TJK: Tajikistan; TLS: Timor-Leste; TTO: Trinidad and Tobago; TUN: Tunisia; TUV: Tuvalu; VNM: Viet Nam; ZAF: South Africa. Not all country codes are shown to make this figure more readable; data for all countries are provided in Table 1.

Fig. 3

The numbers of differences varied considerable within different WHO regions (Fig. 4). The differences between each country’s list and WHO’s model list across therapeutic areas were less when we consider equivalence based on Anatomical Therapeutic Chemical codes (Fig. 5). Algeria, Iran (Islamic Republic of), Mexico and Viet Nam are examples of countries listing large numbers of alternatives to the substances selected by WHO.

Fig. 4.

Differences between national lists of essential medicines and the 2017 WHO Model list of essential medicines

Notes: Differences mean that either a medicine is included on WHO’s model list, but not in that country’s list or a medicine is included on the country’s list, but not in WHO’s model list. No data indicates that no essential medicines list was found in the repository for that country.

Fig. 4

Fig. 5.

Differences between national lists of essential medicines and the WHO’s Model list of essential medicines when medicines in the same chemical subgroup are considered equivalent, 2017

Notes: Differences mean that either a medicine is included on WHO’s model list, but not in that country’s list or a medicine is included on the country’s list, but not in WHO’s model list. We used the Anatomical Therapeutic Chemical classification system to assess equivalence. No data indicates that no essential medicines list was found in the repository for that country.

Fig. 5

For the regression model, we included 136 countries. We excluded the country of Niue because of missing information. The multivariate linear regression indicated that the six included country characteristics explained one-third of the numbers of differences between each country’s list and WHO’s model list (adjusted R2:0.33); WHO region (more differences in the Americas) and health-care expenditure (more differences with higher expenditures) were significantly associated with the total number of differences (P = 0.023; available in a data repository).19 To determine if the main finding (that is, most of the variation in the number of differences was not explained by these country characteristics) depended on the definitions used in the pre-specified analysis, we conducted post-hoc sensitivity analyses. Excluding 17 countries with longer lists that may have been comprehensive formularies rather than essential medicines lists, although they were posted in the essential medicines lists repository, slightly increased the amount of variation in the number of differences explained by the country characteristics (R2: 0.37). Since long national lists will have many differences from WHO’s model list, we performed a sensitivity analysis accounting for list length using the Tanimoto coefficient and the R2 decreased to 0.23 indicating that the main finding is not due to list length. Performing the same analyses using the 2015 WHO model list as the reference, rather than the 2017 version, showed no differences (median of the numbers of differences: 272; IQR: 244 to 367; R2: 0.33).

Between country comparisons

The similarity scores for countries, measuring the extent to which countries tend to list medicines commonly listed by other countries, ranged from −553 to 153 (median: 80; IQR: −45 to 115; Table 1).

Most of the medicines were listed by a relatively small proportion of the countries; 60% (1248/2068) of the medicines were listed by 10% (14) of the countries. Of these 1248 medicines, 250 (20%) were in the same main therapeutic area or the same anatomical subgroup as the closest related medicine on WHO’s model list; 349 (28%) medicines were in the same pharmacological subgroup as the most closely related medicine on WHO’s model list, 611 (49%) medicines were in the same chemical subgroup as the most closely related medicine on WHO’s model list, 30 (2%) medicines were on WHO’s model list, and 8 (1%) medicines could not be classified. The most commonly listed medicines are shown in Table 2. Amoxicillin was listed by all countries and diazepam, doxycycline, short-acting insulin, salbutamol, and metronidazole were each listed by 99% of countries.

Table 2. Most common medicines in countries’ lists of essential medicines, 2017 .

Medicine (synonym) No. of countries list (%) n = 137
Acetazolamide 120 (88)
Acetylsalicylic acid 131 (96)
Acyclovir 129 (94)
Albendazole 112 (82)
Allopurinol 131 (96)
Amiodarone 118 (86)
Amitriptyline 127 (93)
Amoxicillin 137 (100)
Ampicillin 126 (92)
Atenolol 127 (93)
Atropine 127 (93)
Azithromycin 112 (82)
Beclometasone (Beclomethasone) 119 (87)
Benzylpenicillin (Penicillin G) 117 (85)
Betamethasone 126 (92)
Bupivacaine 116 (85)
Calcium 125 (91)
Carbamazepine 134 (98)
Carbidopa 116 (85)
Ceftriaxone 118 (86)
Chloramphenicol 117 (85)
Chlorpromazine 119 (87)
Ciprofloxacin 133 (97)
Clavulanic acid 116 (85)
Cyclophosphamide 114 (83)
Dexamethasone 131 (96)
Diazepam 135 (99)
Diclofenac 121 (88)
Digoxin 132 (96)
Dopamine 113 (82)
Doxycycline 135 (99)
Efavirenz 111 (81)
Epinephrine (Adrenaline) 128 (93)
Erythromycin 126 (92)
Ethambutol 126 (92)
Ethinylestradiol 117 (85)
Fentanyl 113 (82)
Ferrous fumarate 131 (96)
Fluconazole 125 (91)
Folic acid 132 (96)
Furosemide 133 (97)
Gentamicin 133 (97)
Glibenclamide (Glyburide) 122 (89)
Haloperidol 130 (95)
Heparin 125 (91)
Hydrochlorothiazide 130 (95)
Hydrocortisone 133 (97)
Ibuprofen 130 (95)
Insulin, long acting 115 (84)
Insulin, short acting 135 (99)
Isoniazid 127 (93)
Isosorbide dinitrate 119 (87)
Ketamine 113 (82)
Lamivudine 120 (88)
Levodopa 127 (93)
Levonorgestrel 112 (82)
Levothyroxine 130 (95)
Lidocaine (Lignocaine) 134 (98)
Magnesium 127 (93)
Mannitol 113 (82)
Medroxyprogesterone 119 (87)
Metformin 133 (97)
Methotrexate 126 (92)
Methyldopa 123 (90)
Metoclopramide 127 (93)
Metronidazole 136 (99)
Morphine 130 (95)
Naloxone 117 (85)
Neostigmine 119 (87)
Nifedipine 128 (93)
Nitroglycerin (Glyceryl trinitrate) 120 (88)
Nystatin 127 (93)
Omeprazole 127 (93)
Oxytocin (Pitocin) 123 (90)
Paracetamol (Acetaminophen) 133 (97)
Penicillin G Benzathine 119 (87)
Phenobarbital 131 (96)
Phenytoin 118 (86)
Pilocarpine 123 (90)
Potassium 128 (93)
Prednisolone 130 (95)
Propranolol 129 (94)
Pyrazinamide 126 (92)
Ranitidine 125 (91)
Rifampicin 129 (94)
Salbutamol 135 (99)
Spironolactone 131 (96)
Streptomycin 117 (85)
Sulfamethoxazole 130 (95)
Suxamethonium 111 (81)
Tamoxifen 116 (85)
Tetanus vaccine 115 (84)
Timolol 126 (92)
Trimethoprim 132 (96)
Valproic acid (Sodium valproate, Valproate, Valproate semisodium) 127 (93)
Verapamil 118 (86)
Vitamin B1 (Thiamine) 118 (86)
Vitamin B12 (Cobalamin) 125 (91)
Vitamin B6 (Pyridoxine) 125 (91)
Vitamin K (Menadione, Phytomenadione, Phytonadione) 122 (89)
Zidovudine (Retrovir) 118 (86)

Note: We classified medicines listed in more than 80% of national lists as common.

We examined medicines that were expected to be listed by only a small number of countries. There were six treatments for trypanosomiasis (pentamidine, suramin sodium, eflornithine, melarsoprol, nifurtimox, benznidazole) and four antileishmaniasis medicines (amphotericin B, miltefosine, paromomycin, sodium stibogluconate) on WHO’s model list. These medicines were listed by between eight and 96 countries (median: 12; IQR 9 to 24; more information available in a data repository).19

Discussion

We found substantial differences in essential medicines lists. Most national lists of essential medicines had more than 200 differences compared with WHO’s model list. These differences were only partly explained by the countries’ characteristics we investigated. Most of the medicines were listed by a small number of countries. Decision-makers could choose to re-examine whether medicines listed by a small number of other countries should be removed from their national list.

Previous studies have compared many national lists of essential medicines, but for only one therapeutic area. For example, in one study on medications for neuropathic pain listed in the essential medicines lists of 112 countries, only four of 18 differences (22%) were related to country income.20 Gabapentinoids, that can be used to treat neuropathic pain, were more likely to be listed in high-income countries, although the efficacy of these medicines is questionsable.21,22 Other studies have compared lists of several countries for specific populations. For instance, comparing lists for paediatric populations have shown that the Indian and South African essential medicines lists may take better account of the needs of children compared with the Chinese list.23 The findings of these studies are consistent with our study, and also suggest that differences in the lists are not explained by countries’ characteristics, implying there may be opportunities to improve essential medicines lists.

Our study has limitations. We abstracted the medicines in each country’s list of essential medicines from the information posted on WHO’s website, a process that was liable to errors, as documents describing essential medicines lists had to be translated, standard medicine names were not consistently used, and judgements had to be made about what to include in ambiguous cases. In the future, stakeholders could validate and update the information in the data set used for this study and also provide information about how they are using the essential medicines list to the database of global essential medicines.18 Some of the lists included in this study may not be used by the respective countries. Furthermore, the country characteristics we included may not fully capture important features. We relied on the widely used Anatomical Therapeutic Chemical classification system, which like other classifications systems, assigns some medicines with multiple codes for different indications and does not include every medicine in use.

In 2004, WHO stated that the lack of access to essential medicines remains one of the most serious global public health problems and identified the “careful selection of essential medicine [as] the first step in ensuring access.”24 The importance of essential medicines lists will probably grow as countries move towards universal health coverage, as a part of achieving the sustainable development goals.25 Our findings suggest that greater care may be needed in selecting medicines that meet the priority health-care needs of populations. The reasons for the substantial differences from WHO’s model list and the differences between countries should be further studied. Governments could provide explanations for medicines they have decided to add to help other countries decide if they should also list them. Countries could also use the database of global essential medicines created for this study to flag medicines that are not listed by similar countries or in WHO’s model list.18 There may be gaps in the information available to countries about the medicines on WHO’s model list including the evidence supporting listing. Such additional information may help governments to decide if medicines on their lists should be removed or if other medicines should be added. WHO could also provide feedback to countries updating their lists on how their essential medicines lists compare with similar countries and highlight specific medicines for inclusion or removal, based on the decisions made by countries with similar health needs.

Many medicines are considered essential by only a small number of countries, and this difference is not likely explained by differences in health needs in those countries. Future work should determine whether specific changes should be made to particular essential medicines lists and explore the processes for creating and updating essential medicines lists. This may help identify opportunities to improve essential medicines lists and promote appropriate use of medicines in support of universal health coverage.

Acknowledgements

We thank Richard Stevens and Mei-Man Lee of the Nuffield Department of Primary Care Health Sciences, University of Oxford, United Kingdom of Great Britain and Northern Ireland. NP is supported by the Department of Family and Community Medicine, St Michael’s Hospital and the Department of Family and Community Medicine, University of Toronto, Canada, which is designated the WHO Collaborating Centre on Family Medicine and Primary Care.

Funding:

Canadian Institutes of Health Research and Ontario Strategy for Patient Oriented Research Support Unit.

Competing interests:

NP reports grants from Canadian Institutes for Health Research, the Ontario SPOR Support Unit, the Canada Research Chairs program and Physicians Services Incorporated during the conduct of the study. JKA has co-authored and edited textbooks and written reviews, commentaries, and medicolegal reports on various aspects of prescribing, and has sometimes received remuneration. AP reports grants from NIHR, grants from NIHR School of Primary Care Research, during the undertaking of the study; and occasionally receives expenses for teaching Evidence-Based Medicine. CH has received expenses and fees for his media work. CH has received expenses from WHO and holds grant funding from the NIHR Oxford BRC, the NIHR School of Primary Care Research, and is a NIHR Senior Investigator. On occasion, CH receives expenses for teaching EBM and is also paid for his GP work in NHS out of hours. All other authors declare no competing interests.

References


Articles from Bulletin of the World Health Organization are provided here courtesy of World Health Organization

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