Table 4. Patient flow through studies included in the systematic review.
| Study | Inclusion criteria | Exclusion criteria | Patients in final analysis/total number of patients | Reasons for exclusion (if applicable) |
|---|---|---|---|---|
| Sawasdivorn 2001 [18] | Ages not specified Provisional diagnosis of dengue infection or suspected dengue infection. Parental consent. |
Not specified | 176/176 | N/A |
| Martinez 2005 [19] | Age >12 years <96h of fever Informed consent Diagnostic impression of dengue or unspecified viral infection. |
Clinical evidence of another infectious process that partially or totally explains the current disease. Diabetes, AIDS, cirrhosis, rheumatological or malignant disease, heart or kidney failure, or history of corticosteroid use. Residence in a rural area or with difficult access for monitoring. |
190/190 | N/A |
| Gan 2011 [20] | Suspected dengue cases | Not specified | 162/205 | Lack of paired sera or elevated IgM/IgG without seroconversion—43 |
| Lagi 2011 [21] | Not specified | Missing clinical or lab data | 109/109 | N/A |
| Fonseca 2012 [22] | Not specified Convenience sample |
Not specified | 1490/1490 | N/A |
| Nujum 2012 [23] | Ages not specified 2–7 days of acute febrile illness Household surveys around confirmed dengue cases and corresponding primary/secondary care settings |
Definite diagnosis Informed consent not given |
254/254 | N/A |
| Capeding 2013 [24] | Age 2–14 years on the day of enrolment >2 days fever Able to attend scheduled visits/comply with study procedures |
History of chronic illness/immunodeficiency Pandemic influenza vaccination in 2 weeks before/after enrolment Any other vaccination in 4 weeks before/after enrolment |
358/374 febrile episodes 1487/1500 patients |
Voluntary withdrawal– 12 Noncompliant with protocol -1 Missing lab diagnosis—42 |
| Daumas 2013 [25] | Age >12 years ≤3 days fever For emergency department study: first 8 patients, once a week |
Severe illness (i.e. with altered consciousness, signs of shock or severely dehydrated) in need of emergency care Evident or suspected focus on clinical examination (e.g. tonsillitis, pyelonephritis) |
142/182 | Indeterminate test result—40 |
| Gutiérrez 2013 [14]–cohort study | Age 2–15 years ≤6 days fever without apparent origin Part of Paediatric Dengue Cohort Study |
Not specified | 3407/3617 | Missing confirmed lab result—210 |
| Gutiérrez 2013 [16]–Hospital study | Age 6 months– 14 years <7 days fever Inpatients/outpatients 1+ of: headache, arthralgia, myalgia, retro-orbital pain, positive tourniquet test, petechiae or other signs of bleeding. |
Defined focus other than dengue Weight <8 kg Age >6y with signs of altered consciousness at the time of recruitment and thus unable to provide assent |
1160/1210 | Indeterminate lab results—50 |
| Gan 2014 [26] | Age ≥18 years Fever >37.5°C |
Pregnancy Alternative syndromic diagnosis for febrile illness |
197/246 | Point-of-care test not performed– 2 Inconclusive reference standard—47 |
| Nujum 2014 [27] | Age >5 years 2–7 days fever |
Already diagnosed as dengue Not giving informed consent Definitive diagnosis/focus of infection |
851/939 | Consent not given—89 |
| Pitisuttithum 2015 [28] | All patients with dengue recorded as an adverse event/severe adverse event. All individuals without a dengue diagnosis and a severe adverse event using a preferred term that corresponded to the system organ class “Infections and infestations” or idiopathic fever (pyrexia) occurring between June and September (missed dengue cases) |
Missing acute/convalescent blood sample Diagnoses with a known cause Individuals whose samples were identified as controls for the immune correlates study |
121/124 dengue events 72/77 non-dengue SAEs |
Missing serology specimens—8 |
| Nealon 2016 [29] | 2–14 years CYD14 vaccine trial participant Fever ≥ 38°C on ≥ 2 consecutive days |
Not specified | 3099/3099 febrile episodes | N/A |
| Seshan 2017 [30] | Acute undifferentiated febrile illness | Not specified | 150/150 | N/A |
| Caicedo 2019 [17]–Aedes Network | Ages not specified <96h fever of unknown origin/suspected dengue Dengue diagnosis in the first 24h of hospitalisation |
Concomitant diseases | 987/987 | N/A |
| Caicedo 2019 [17]–National Public Health Surveillance | National Public Health Surveillance system notification sheets | Not specified | 461/461 | N/A |
| STUDIES USING MODIFIED CRITERIA | ||||
| Peragallo 2003 [31] | Troops returning to Italy after 3-month period of duty in East Timor | Not specified | 241/280 | Not specified |
| Juárez 2005 [32] | Clinical picture compatible with an infectious process Received National Institute of Health diagnostic tests Patient recorded in PHLIS database |
Incomplete records Diagnostic test not specified Yellow fever vaccination <10d before symptom onset |
315/479 | Not specified |
| Low 2011 [33] | Age ≥18 years <72h of fever >37.5°C |
Not specified | 2129 | Not specified |
| Wieten 2012 [34] | All patients who were serologically tested for dengue at the AMC between 2006 and 2011 | Treated outside the AMC Double tests Missing files Onset of symptoms >6 months before consultation No travel history |
409/1124 | Treated outside the AMC—200 Double tests– 285 Missing files– 31 Onset of symptoms >6 months before consultation– 14 No travel history– 13 Indeterminate results– 172 |
| Ridde 2016 [35] | Fever >38°C at survey or during the previous week Negative rapid diagnostic test for malaria |
Not specified | 379/379 | N/A |
| Bodinayake 2018 [36] | Age ≥1 year Admitted to a medical or paediatric non-surgical ward with documented fever (>38°C) at presentation or within 48 hours of hospital admission |
Hospitalized for >48 hours Hospitalized/underwent surgery in the previous 7 days Unable/unwilling to give consent |
838/877 | Inconclusive results—39 |