Supplementary material, table 1: Descriptive information on population-based data sources identified by the literature search

Relevant, Ascertainment Study population & Reference potentially Study design Study date Study site of causes of sample size relevant death

Kishamawe et al. Health & Demographic Surveillance System HDSS (longitudinal surveillance system with repeated From 1994. VA from Feb Kisesa ward (all 7 villages), Magu All residents (N = Profile: The Magu Health and Demographic Surveillance System. Relevant VA (ICD-10) censuses, continuous birth & death notifications) 1995. district, 35,569 in 2014) Int J Epi 2015; 44:1851-61.

Mrema et al. Health & Demographic Surveillance System Profile: HDSS (longitudinal surveillance system with repeated Rufiji district (38 villages), Pwani All residents (N = The Rufiji Health and Demographic Surveillance System. Int J Epi Relevant From 1998. VA from 1999 VA (ICD-10) censuses, continuous birth & death notifications) region 103,503 in 2012) 2015; 44: 472-83. Across Kilombero & Ulanga All residents (N = Geubbels et al. Health & Demographic Surveillance System From 1996. VA from 2000 districts (25 villages), Morogoro HDSS (longitudinal surveillance system with repeated 126,836 in 2012) Profile: The Ifakara Rural and Urban Health and Demographic Relevant region VA (ICD-10) censuses, continuous birth & death notifications) Surveillance System. Int J Epi 2015; 44:848-61 Ifakara town (5 areas), Kilombero All residents (N = From 2007. VA from 2007 district, 44,992 in 2012)

Kamugisha et al. Establishing and implementing Demographic Surveillance System as a tool for monitoring health HDSS (longitudinal surveillance system with repeated Korogwe district (14 villages across All residents (N = Relevant From 2005. VA from 2005 VA (ICD-10) interventions in Korogwe District, north-eastern . censuses, continuous birth & death notifications) 3 wards), 25,264 in 2005) Tanzan J Health Res 2011; 13: 57-67.

* city (Ilala & Adult Morbidity and Mortality Project (AMMP): Moshiro et al. The importance of injury as a cause of death in Temeke districts) * Morogoro Longitudinal surveillance system with repeated All residents (N = sub-Saharan Africa: results of a community-based study in Relevant From 1992 Rural district (61 villages), VA (ICD-10) censuses (annual or semi-annual), continuous birth & 307,912 inhabitants) Tanzania. Public Health 2001; 115: 96-102. Morogoro region * Hai district (51 death notifications villages),

Tanzanian Sentinel Panel of Districts (SPD): SAVVY Nationally representative sample Nationally Kabadi et al. Data Resource Profile: The sentinel panel of (Sample Vital registration with Verbal autopsY): of 23 districts in the mainland, representative sample districts: Tanzania's national platform for health impact Relevant Longitudinal surveillance system with repeated From Mar 2011 VA (ICD-10) excluding districts under of households (N = evaluation. Int J Epi 2015; 44:79-86. censuses (every 5 years), continuous birth & death demographic surveillance 644,217) notifications

Muheza district (non-random Kamugisha et al. Malaria specific mortality in lowlands and Cross-sectional household survey: Enumeration of all sample of 4 villages in highland All residents (sample highlands of Muheza district, north-eastern Tanzania. Tanzan Relevant households with a history of death (2 years recall Not reported VA areas & 4 villages in lowland size not reported) Health Res Bull 2007; 9: 32-7. period) areas), Tanga region * Lindi Rural, Nachingwea and Hanson et al. Maternal mortality and distance to facility-based Cross-sectional household survey: Enumeration of all Ruangwa districts (all villages), obstetric care in rural southern Tanzania: a secondary analysis Potentially households, live births history in all WRA (5 years All residents (N = Jun - Oct 2007 * Newala and VA (ICD-10) of cross-sectional census data in 226 000 households. Lancet relevant recall period), history of deaths in the household (Jan 818,583) Tandahimba districts (all villages), Glob Health 2015; 3: e387-95. 2004 to June 2007) Muleba district (random sample of Kaatano et al. Patterns of malaria related mortality based on Cross-sectional verbal autopsy survey: Enumeration Potentially 3 villages in epidemic areas & 3 All residents (sample verbal autopsy in Muleba District, north-western Tanzania. of all households with a history of death (July 1997 to Not reported VA (ICD-10) relevant villages in non-epidemic areas), size not reported) Tanzan J Health Res 2009; 11: 210-8. June 2006) region Dark grey lines indicate data sources for which no response was received at the data acquisition stage and without information on drowning death reported in the publication Light grey lines indicate data sources re-classified as not relevant at the data acquisition stage 1 Supplementary material, table 2: Descriptive information on hospital-based data sources identified by the literature search

Relevant, Ascertainment Reference potentially Study design Study date Study site Sample size of causes of relevant death Kipsaina et al. Mortuary based injury surveillance for low-mid Medical Mortuary-based fatal injury surveillance system pilot From Sep 2010 to Feb 1,500 deaths, 180 injury income countries: process evaluation of pilot studies. Injury Relevant Not reported record (ICD- study 2011 deaths 2015; 46: 1509-14. 10) ** 5 hospitals in Dar es Salaam: * Muhimbili referral hospital * Murray et al. Population Health Metrics Research Consortium Medical Mwananyamala district hospital * gold standard verbal autopsy validation study: Design, Prospective review of "high quality" medical records From Jan 2007 to Dec record (gold Relevant Temeke district hospital * Hindu 4,061 deaths implementation, and development of analysis datasets. Popul (eligible causes of death) 2010 standard), VA Mandal private hospital * Ocean Health Metr 2011; 9: 27. (ICD-10) Road Cancer Institute ** All 4 public hospitals on Pemba island

6 hospitals: * Muhimbili Orthopaedic Institute, Dar es Salaam * Morogoro regional 9,316 injuries, 120 Boniface et al. Injury experience in Tanzania - Need for Prospective review of medical records (admissions of From Nov 2011 to Dec hospital * Kigoma regional hospital Medical Relevant deaths (0 drowning intervention. East Afr Med J 2013; 90: 171-9. injury patients at casualty departments) 2012 * Mtwara regional hospital * record death) Musoma regional hospital * Korogwe district hospital, Tanga region

All health facilities in a nationally Kabadi et al. Data Resource Profile: The sentinel panel of Tanzanian Sentinel Panel of Districts (SPD): FBIS representative sample of 23 1,608 dispensaries, 193 Potentially Monthly visits from Jan Medical districts: Tanzania's national platform for health impact (Facility-Based Information System): Aggregated districts in the mainland, excluding health centres, 87 relevant 2010 record evaluation. Int J Epi 2015; 44:79-86. DHIS-2 routine facility data districts under demographic hospitals surveillance

4 hospitals in Dar es Salaam: * Mutasingwa et al. Injury registration in a developing country. A Muhimbili Medical Centre * Potentially Retrospective review of medical records (inpatient 1,098 acute injuries (0 Medical study based on patients' records from four hospitals in Dar es From Jan to Dec 1998 Muhimbili Orthopedic Institute * relevant admissions with acute injury, outpatients excluded) drowning case) record Salaam, Tanzania. Cent Afr J Med 2011; 47: 203-9. Agakhan hospital * Mission Mikocheni hospital Bugando Medical Centre referral 3,340 injuries (25 Rutta et al Epidemiology of injury patients at Bugando Medical Potentially Retrospective review of medical records (injuries at Medical From 1995 to 1997 hospital in Mwanza, Mwanza drowning cases), 73 Centre, Tanzania. East Afr Med J 2001; 78: 161-4. relevant surgical, clinic, casualty, radiology, theatre wards) record district, Mwanza region deaths Cox et al. Emergency medicine in a developing country: Kilimanjaro Christian Medical Potentially Retrospective review of medical records (admissions From Jul 2005 to Jan Medical experience from Kilimanjaro Christian Medical Centre, Tanzania, Centre referral hospital in Moshi, c. 400 injury casualties relevant at casualty department, outpatients excluded) 2006 record East Africa. Emerg Med Australas 2007; 19: 470-5. Moshi district, Kilimanjaro region

2 6 hospitals in : * Chakechake * Mkoani * Wete Aregawi et al. Reductions in malaria and anaemia case and death district hospitals in Zanzibar * Potentially Retrospective review of medical records (outpatient Medical burden at hospitals following scale-up of malaria control in From 1999 to 2008 Kivunge * Makunduchi primary relevant attendances, inpatient admissions) record Zanzibar, 1999-2008. Malar J 2011; 10: 46. health care centres on Unguja island * Micheweni primary health care centre on Pemba island Casualty room: From Jan Sawe et al. Trends in mortality associated with opening of a full- 2008 to Dec 2009; ED 753 deaths, of whom 53 Potentially Retrospective review of medical records (admissions Muhimbili National Hospital in Dar Medical capacity public emergency department at the main tertiary-level opening in Jan 2010: trauma (non-road traffic relevant at the casualty room and emergency department) es Salaam record hospital in Tanzania. Int J Emerg Med 2015; 8: 24. From Feb 2010 to Dec accidents) deaths 2011 10 "voluntary agency" hospitals: * Maegga et al. Malaria in the southern highlands of Tanzania: a Isoko * Mbozi * Chimala * Igongwe review of hospital records. Tanzan Health Res Bull 2005; 7: 125- Potentially Retrospective review of medical records (outpatient * Itete, * Ilembula * Medical From 1986 to 2000 32. relevant attendances, inpatient admissions) * Consolata Ikonda * record Bulongwa * St John Lugalawa, region

Prospective review of medical records (paediatric Simon et al. Paediatric injuries at Bugando Medical Centre in Bugando Medical Centre referral Potentially injury admissions at AE department and paediatric From Aug 2011 to Apr 150 paediatric (1 month Medical North-western Tanzania: A prospective review of 150 cases. J hospital in Mwanza, Mwanza relevant surgical ward, patients without next of kin to consent 2012 to 10 years old) injuries record Trauma Manag Outcomes 2013; 7: 10. district, Mwanza region and deaths before complete assessment excluded) Peck et al. Hypertension-related diseases as a common cause of Bugando Medical Centre referral 11,045 adult (> 12 years Potentially Prospective review of medical records (admissions at From Jan 2009 to Dec Medical hospital mortality in Tanzania: a 3-year prospective study. J hospital in Mwanza, Mwanza old) admissions, 2,049 relevant adult medical wards) 2011 record Hypertens 2013; 31: 1806-11. district, Mwanza region deaths Medical Mgaya et al. Suicide in the Dar es Salaam region, Tanzania, 2005. Potentially Prospective review of medical records (suicide Muhimbili National Hospital in Dar 1,500 autopsies (1,420 From Jan to Dec 2005 record, J Forensic Leg Med 2008; 15: 172-6. relevant deaths at mortuaries) es Salaam medico-legal) autopsy Prospective review of medical records (violent deaths Outwater et al. Homicide death in Dar es Salaam, Tanzania Potentially Muhimbili National Hospital in Dar 458 intentional injury Medical - homicide, suicide, and police perpetrated deaths - 2005 2005. Int J Injury Cont Saf Prom 2008; 15: 243-52. relevant es Salaam deaths record at mortuaries) Dark grey lines indicate data sources for which no response was received at the data acquisition stage and without information on drowning death reported in the publication Light grey lines indicate data sources re-classified as not relevant at the data acquisition stage

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Supplementary material, table 3: Descriptive information on report-based data sources identified by the in- country networking

Potentially Government institution's name relevant or Data source relevant Electronic annual reports on maritime accidents/ sunken vessels (> 4 m) Ministry of Transport -Surface and Marine Relevant in the Tanzanian territorial water with number of passengers in Regulatory Authority (SUMATRA) destress, rescued and missing

Electronic annual reports on maritime accidents/ sunken vessels (> 4 m) Zanzibar Marine Authority (ZMA) Relevant in the Zanzibar territorial water with number of passengers in destress, rescued and missing

Potentially Ministry of Water and Irrigation Electronic and paper-based annual reports on specific zones/basins relevant

Prime Minister office - Disaster Management Potentially Paper-based annual reports on all national level disasters Department relevant

Potentially Electronic and paper-based annual reports with notification of deaths Ministry of Home Affairs relevant reported to the police

Potentially Tanzania Meteorogical Authority (TMA) Electronic annual reports on disasters related to climate relevant

Potentially Ministry of Fisheries Paper-based annual reports on small (< 4 m) vessels & water basins relevant

Potentially Information on near drowning, drowning deaths of fishermen (vessels < Beach management unit (BMU) relevant 4 m) Dark grey lines indicate data sources for which no response was received at the data acquisition stage Light grey lines indicate data sources re-classified as not relevant at the data acquisition stage

4 Supplementary material, table 4: Drowning mortality estimates by sex and by data source

Males Females Drowning related ICD- Total Annual average Total Annual average Data source Time period Total all- Total Drowning Total all- Total Drowning 10 codes population drowning population drowning cause drowning fraction cause drowning fraction (range) (annual mortality rate/ (annual mortality rate/ deaths deaths (%) deaths deaths (%) average) 100,000 average) 100,000

Population-based data

Ifakara urban HDSS Jan 2008 - V90-Y21 1,163 6 0.52 18,644 4.6 1,181 3 0.25 21,125 2.0 (Geubbels et al., 2015) Dec 2014

Ifakara rural HDSS Jan 2008 - V90-Y21 3,199 32 1.00 59,491 7.7 2,989 24 0.80 60,823 5.6 (Geubbels et al., 2015) Dec 2014

Rufiji HDSS Jan 2008 - V90-Y21 2,601 17 0.65 47,281 5.1 2,690 11 0.41 51,283 3.1 (Mrema et al., 2015) Dec 2014

SAVVY survey, 22 districts across the Jan 2008 - mainland V90-Y21 8,416 103 1.22 272,883 9.4 6,917 40 0.58 287,412 3.5 Dec 2014 (Kabadi et al., 2015)

Muleba district, Kagera region Jul 1997 - V90-Y21 202 3 1.49 - - 217 0 0.00 - - (Kaatano et al., 2009) Jun 2007

Hospital-based data

5 hospitals in Dar es Salaam Nov 2006 - - 1,569 19 1.21 - - 1,670 3 0.18 - - (Murray et al., 2011) Dec 2010

4 hospitals on Pemba island Jan 2007 - - 428 25 5.84 - - 390 9 2.31 - - (Murray et al., 2011) Dec 2010

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