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Rapid Systematic Review of the Safety of MMRV Vaccine
A. Background
The measles -mumps -rubella -varicella (MMRV) vaccine (ProQuad, Merck) was licensed in the
United States in 2005 for use in children 12 months through 12 years of age. While not licensed
for use in the United States, Priorix -Tetra, a MMRV vaccine manufactured by GlaxoSmithKline ,
first received licensing in some European countries in 2006, and in Canada in 2007. Both
ProQuad and Priorix -Tetra are tetravalent vaccines with similar measles, mumps, rubella and
varicella viral strain composition. [1] Henceforth, any reference to MMRV in this report refers to
ProQuad, unless otherwise specified.
In 2006, the Advisory Committee on Immunization Practices (ACIP) noted that use of
combination vaccines, like MMRV, was preferred over separate injections of equivalent component vaccines (e.g., MMR vaccine and varicella vaccine [MMR+V] ).[2] Post- licensure
safety surveillance data indicated an increased risk for febrile seizures following the administration of the first dose of MMRV among children aged 12- 23 months compared to
those receiving separate MMR and varicella vaccines. [3] Based on this data, ACIP and the
Centers for Disease Control and Prevention updated its guidance to note that the first dose of
MMR and varicella vaccines are preferred to be given separately in this age group, but MMRV
may be used as a first dose in chi ldren aged 12 -47 months based on parent or caregiver
preference. [4] Given the importance of maintaining a thorough awareness and assessment of
MMRV vaccine safety publications, we propose a review of the literature assessing MMRV
vaccine safety to inform the public and healthcare providers, and aid in public health policy discussions.
B. Methods
B.1. Key Question Development
The below question is formulated according to the P I/ECO(ST) strategy, and for this review,
those elements include and are not limited to those identified in Table 1.
1. For children aged 12 months to 12 years, what is the safety of MMRV vaccine?
Table 1
PI/ECO(ST) Criteria for Key Question
PI/ECO(ST)
Element Criteria
Population Pediatric population that includes:
o Infants and toddlers aged 12 months – 23 months
o Young children and children aged 12 months – 12 years
Intervention or
Exposure MMRV vaccination. Including ProQuad, Priorix -Tetra, and brand
unspecified.
Comparator (if
applicable) Any or none
Outcome(s) Adverse events
PI/ECO(ST)
Element Criteria
Adverse outcomes
Safety outcomes
Side effects
Setting Any
Time Frame Any publication years
B.2. Literature Search
A CDC informationist (J.T.) developed search strategies from the Key Question and PI/ECO
criteria, and performed the search in MEDLINE, EMBASE, CINAHL, and Cochrane Library from the start of each database to August 1, 2025. Search strategies and results ar e provided in
Table 3 in the Appendix .
B.3. Study Selection
Results of the literature searches were uploaded into EndNote 21 (Clarivate Analytics©, Thomson Reuters, New York, NY, USA), duplicate records were removed, and unique titles and abstracts were uploaded to Covidence (Veritas Health Innovation Ltd., Melbourne, VIC, Australia) where a second round of deduplication was conducted. Three reviewers (JR, EQ, JS)
independently screened all titles and abstracts and removed irrelevant references;
disagreements were resolved by consensus . Relevant full texts were scre ened independently
by three reviewers (JR, EQ, JS); disagreements were resolved by consensus. All studies were screened according to the pre -identified exclusion criteria below, and results of the study
selection process are provided in Figure 1 .
Criteria for excluding studies from the literature review include:
1. No full text available;
2. Not available in English;
3. Pre-licensure clinical trials;
4. Not relevant to key question;
5. No primary data or analysis, or secondary data not systematically collected;
6. Insufficient methodologic reporting (i.e., meeting abstract or poster);
7. Study population includes participants <12 months or >12 years of age; or
8. Indeterminate age range of study population receiving vaccine.
Figure 1. Results of the Study Selection Process
Identification
Studies screened (n = 326)
Studies sought for retrieval (n = 117 )
Studies assessed for eligibility (n = 117 ) References removed (n = 8)
Duplicates identified manually (n = 8 )
Duplicates identified by Covidence (n = 0 )
Marked as ineligible by automation tools (n = 0)
Other reasons (n = 0 )
Studies excluded (n = 191 )
Studies excluded (n = 107 )
Pre-licensure clinical trial (n = 40)
No English translation available (n = 1 )
No vaccine safety outcomes assessed (n = 5)
Wrong study design, including
commentary/editorial , case report, case series
without primary analysis (n = 11 )
Coadministration of intervention with other
vaccines (n = 4 )
Wrong intervention (intervention -specific data
not included in study) (n = 20)
Study participants age not limited to 12 months
to 12 years (n = 6 )
Studies included in review (n = 10)
Screening Studies from databases/registers (n = 334 )
Embase (n = 200)
MEDLINE (n = 111)
Cochrane Library (n = 20)
CINAHL (n = 3 )
B.4. Data Extractio n and Outcome Summarization
Data from studies meeting inclusion criteria were independently extracted by four reviewers using
a standardized Microsoft Excel (2021) form, and differences were reconciled by discussion. Outcome data were extracted as presented in the studies. For the purposes of this review,
statistical significance was defined as p ≤ 0.05. The evidence was summarized and synthesized for
each outcome domain.
C. Summary of Evidence
C.1. Summaries of Evidence
A review of literature was conducted addressing safety of MMRV vaccine (ProQuad or Priorix -Tetra ).
This review focused on the v accine safety for children aged 12 months to 12 years of age. Priorix -
Tetra is not licensed for use in the United States, but was included in the review due to a similar
viral strain composition as the ProQuad formulation and a desire to report on comprehensive
MMRV safety data . Additionally, this review focused on safety data related to post- licensure
studies, and did not include studies that did not present data on MMRV administration without
other vaccines coadministered on the same day. Refer to Secti on B3 for full exclusion criteria for
this review. The 10 studies reviewed are listed in Table 2. In the narrative text below , studies
performed in the United States are presented first, and have a brief summary introduction for each
outcome discussed ; studies performed outside of the United States are briefly summarized under
the international heading s.
Table 2
Characteristics of studies meeting inclusion criteria
Lead a uthor
last name ,
year of
publication Study design MMRV trade
name
(ProQuad or
Priorix -
Tetr a) Data
collection period Sample
size, N Surveillance
system (if applicable) Country
Cocchio,
2016[5] Prospective
cohort Priorix -Tetra August 1,
2013 – July
31, 2014 10395 Not reported Italy
Deichman,
2015[6] Randomized
comparative
study ProQuad January 12,
2007 –
February 13,
2008 947 Not reported Germany
and Italy
Haas, 2019 [7] Randomized
comparative
study ProQuad Pre-2019,
otherwise not defined 405 Not reported France
Hambidge,
2014[8] Self -controlled
case series ProQuad 2004 – 2010 5667 Vaccine Safety
Datalink United
States
Jacobsen,
2009[9] Retrospective
cohort ProQuad February
2006 – June
2007 62596 Kaiser
Permanente
Southern
California
electronic data
system United
States
Klein,
2010[10] Self -controlled
case series ProQuad 2000 – 2008 459461 Vaccine Safety
Datalink United
States
Klein,
2012[11] Retrospective
cohort ProQuad 2006 -2008
for MMRV
2000 – 2008
for MMR + V 154188 Vaccine Safety
Datalink United
States
MacDonald,
2014[12] Retrospective
cohort Priorix -Tetra 2006 – 2012 277774 Canadian
Institute for Health
Information
database Canada
O’Leary,
2011[13] Self -controlled
case series ProQuad 2000 – 2009 1.8 million Vaccine Safety
Datalink United
States
Rowhani -
Rahbar,
2013[14] Retrospective
cohort ProQuad 2001 -2011 840348 Vaccine Safety
Datalink United
States
Table 3
Selected outcomes reviewed in studies meeting inclusion criteria
Lead author last name,
year of publication MMRV trade
name (ProQuad
or Priorix -Tetra) Country Outcome(s) summarized
Cocchio, 2016 [5] Priorix -Tetra Italy Febrile seizure, afebrile seizure, fever,
irritability, parotid swelling, arthralgia,
local reaction s (pain, swelling,
redness )
Deichman, 2015 [6] ProQuad Germany and Italy Febrile seizure, fever, irritability, local
reactions (pain, swelling, redness)
Haas, 2019 [7] ProQuad France Fever, mumps -like illness
Hambidge, 2014 [8] ProQuad United States Seizure (not otherwise specified)
Jacobsen, 2009 [9] ProQuad United States Febrile seizure
Klein, 2010 [10] ProQuad United States Febr ile seizure
Klein, 2012 [11] ProQuad United States Febrile seizure , fever
MacDonald, 2014 [12] Priorix -Tetra Canada Seizure (not otherwise specified)
O’Leary, 2011 [13] ProQuad United States Immune thrombocytopenic purpura
Rowhani -Rahbar, 2013 [14] ProQuad United States Seizure (not otherwise specified ),
fever
Neurologic al outcomes
Febrile seizure
One retrospective cohort (Jacobsen, 2009) and one self- controlled case series within the
Vaccine Safety Datalink (VSD) (Klein, 2010) suggested an increased risk for febrile seizures
following MMRV vaccination compared to separately administered MMR and varicella vaccines on
the same day in children aged 12 -60 months and children aged 12 -23 months, respectively.
Another retrospective cohort within VSD (Klein, 2012) suggested that MMRV and MMR + V were not
associated with increased risk of febrile seizures among children aged 4 -6 years old.
• Retrospective cohort (Jacobsen , 2009) of 62596 children aged 12 -60 months who either
received MMRV vaccination (n=31298) or MMR+V vaccination given separately at the same visit
(n=31298). The study identified 84 cases of confirmed febrile convulsion; there were 1.41/1000
(n=44) confirmed febrile convulsion diagnoses in the MMRV cohort, and 1.28/1000 (n=40) confirmed febrile convulsion diagnoses in the MMR+V cohort. The analysis suggested no
significant difference between MMRV and MMR+V in confirmed febril e convulsion in the 30
days following vaccination (RR=1.1 [95% CI, 0.72 -1.69]). In days 5 -12 following vaccination, the
study identified 32 cases of confirmed febrile convulsion, with 0.7/1000 (n=22) confirmed
febrile convulsion diagnoses in the MMRV cohort, and 0.32/1000 (n=10 ) confirmed febrile
convulsion diagnoses in the MMR+V cohort; there was a suggested increased risk in the MMRV
cohort in the 5 -12-day post -vaccination window (RR=2.2 [95% CI, 1.04 -4.65]).
• Self-controlled case series (Klein , 2010) analyzed 459461 healthy children aged 12 -23 months
within VSD , comparing MMRV vaccine recipients (n=83107) to recipients of MMR + V vaccines
given on the same day (n=376354). The analysis suggested an increased risk for febrile seizures
after MMRV compared to separately administered same -day MMR and V vaccines (RR= 1.98
[95% CI, 1.43 -2.73]); the excess risk per 10,000 doses was 4.6 (95% CI, 2.8 -5.9).
• Retrospective cohort study (Klein , 2012) of 154188 children aged 4 -6 years within VSD analyzed
whether MMRV (n=86750) or same -day MMR+V (n=67438) affects risk for febrile seizure. There
was one febrile seizure 7 -10 days after MMRV and 0 after MMR+V. Febrile seizure risk was 1 per
86750 MMRV doses (95% CI, 1 per 3426441, 1 per 15570), and 0 per 67438 MMR+V doses (95%
CI, 0, 1 per 18282).
Seizure (not otherwise specified)
A self -controlled case series within VSD (Hambidge, 2014) suggested an association of more
postvaccination seizures in delayed MMRV vaccination (administered between age 12-15 months )
compared to on- time MMRV vaccination (administered between age 16-23 months) .
A retrospective cohort within VSD (Rowhani -Rahbar , 2013) found that the incidence of seizures
during the 7 -10 days following immunization with MMRV was significantly greater than that
following immunization with MMR with or without varicella administered separately on the same
day. The study suggested a 2 -fold increase in the risk of seizures in the 7 -10 days following MMRV
vaccination compared with MMR administered with or without varicella vaccine in both younger (12
to 15 months of age) and older childr en (16 to 23 months of age).
• Self-controlled case series within VSD (Hambidge , 2014) analyzed timely versus delayed early
childhood vaccination in a cohort of 5667 children with diagnosis of first seizure between 38 and 730 days of life. For on -time MMRV vaccination (administered at age 361 – 488 days), the
IRR for seizure in the 7 -10 day s after vaccination was 4.95 (95% CI, 3.68 -6.66). For delayed
receipt of MMRV (administered at age 489 -730 days), the IRR was 9.8 (95% CI, 4.35 -22.06). The
vaccine -seizure association was most pronou nced if MMRV vaccine was administered
between 16 and 18 months of age (IRR 11 [95% CI, 4.26 -28.38]).
• Retrospective cohort study within VSD (Rowhani -Rahbar , 2013) examined the effect of age on
the risk of fever and seizures following immunization with measles- containing vaccines in
children aged 12 to 23 months of age (N =840348). A MMRV vs MMR +/ - V cohort analysis in
participants aged 12 -15 months indicated an in creased risk in seizures among MMRV
recipients (IRR 2.0 [95% CI, 1.4 -2.8]), with an excess risk of 4.2 cases per 10000 doses (95% CI,
1.8-16.3). A MMRV vs MMR +/- V cohort analysis in participants aged 16 -23 months indicated an
increased risk in seizures among MMRV recipients (IRR 2.1 [95% CI, 1.3 -3.3]), with an excess
risk of 9 cases per 10000 doses (95% CI, 1.8 -16.3). The relative risk of seizure during the 7 -10
days following MMRV immunization (MMR with or without varicella administered separately on
the same day as the reference) was not statistically different between children 16 to 23 months
of age and those 12 to 15 months of age. The attributable risk of seizures during the 7 -10 days
following MMRV immunization (MMR with or without varicella admi nistered separately on the
same day as the reference) was greater among children 16 to 23 months of age than among
children 12 to 15 months of age; however, the difference did not gain statistical significance .
MMRV vaccine safety in international settings – Neurological outcomes
• One prospective cohort from Italy (Cocchio , 2016) of 10395 healthy fourteen -month old
children eligible for their first vaccination against measles, mumps, rubella, and varicella assessed adverse events relating to two different vaccination strategies: Priorix -Tetra
vaccination (n=5265) or separate MMR and varicella vaccination administered on the same day
(n=5130). This study repor ted no difference in risk of febrile seizure following MMR + V
compared to Priorix -Tetra [RR 0.80 (95% CI, 0.30 -2.15)] or afeb rile seizure following MMR +
V compared to Priorix -Tetra [RR 2.05 (95% CI, 0.18 -22.6)].
• One randomized comparative study (Deichmann, 2015) of 947 healthy German and Italian
children aged ≥12 to <24 months randomly assigned the children to one of three vaccination
arms in a 2:1:1. Group 1 received one MMRV dose and one hexavalent vaccine concomitantly
at separate injection sites, group 2 received MMRV only, and group 3 received the hexavalent
vaccine only. In the MMRV -only group (n=234), no participants were reported to have febrile
convulsion within 0 -28 days following vaccination .
• One retrospective cohort study from Canada (MacDonald , 2014) compared the risk of
seizures after the first dose of Priorix -Tetra with the risk after same -day administration of
separate MMR + V in 277774 children aged 12 to 23 months. The risk of seizures 7 -10 days
after vaccination was twice as high with Priorix -Tetra as with MMR + V (RR 1.99 [95% CI,
1.3-3.05]). The excess absolute risk of seizures was 3.52 seizures per 10000 doses of
Priorix -Tetra relative to MMR_V. In high -risk children (those with a pe rsonal history of febrile
seizure; seizure disorder; central nervous system injury, infection or neoplasm;
encephalopathy; or a progressive, evolving or unstable neurologic condition), the risk was not
differentially higher fo r Priorix -Tetra (RR 1.3 [95% CI, 0.6 -2.79]).
Systemic reaction outcomes
Fever
A retrospective cohort within VSD (Klein, 2012) reported that there was no apparent peak in
outpatient fever visits during days 7 to 10 after MMRV, MMR or varicella vaccines , and that
outpatient fever visits 7 to 10 days were not significantly higher after MMR + V than after MMR
alone, although there was a trend in that direction.
Another retrospective cohort study within VSD (Rowhani -Rahbar, 2013) found that the
incidence of fever during the 7 -10 days following immunization with MMRV was significantly greater
than that following immunization with MMR with or without varicella administered separately on
the same day. The study suggested a 1.4-fold increase in the risk of fevers in the 7 -10 days
following MMRV vaccination compared with MMR administered with or without varicella vaccine in
both younger (12 to 15 months of age) and older children (16 to 23 months of age).
• The Klein (2012) r etrospective cohort within VSD reported o utpatient fever visits for MMRV
recipients occurred at an adjusted rate of 5.2 per 100 person- years (95% CI, 3.9 -6.8)) in the 7 -
10-day post -vaccination window, and 5 per 100 person- years (95% CI, 4.5 -5.4) in the 0 -42-day
post -vaccination window. Outpatient fever visits for MMR+V recipients occurred at an adjusted
rate of 8.8 per 100 person -years (95% CI, 6.2 -12) in the 7 -10-day post -vaccination window, and
6.4 per 100 person -years (95% CI, 5.7 -7.2) in the 0 -42-day post -vaccination window.
• The Rowhani -Rahbar (2013) r etrospective cohort within VSD reported that a MMRV vs MMR +/ -
V cohort analysis in participants aged 12 -15 months indicated an increased risk in fever among
MMRV recipients (IRR 1.4 [95% CI, 1.3 -1.5]), with an excess risk of 8.9 cases per 10000 doses
(95% CI, 3.2 -15.2); in a cohort of participants age d 16 -23 months the IRR was 1.4 (95% CI, 1.1 -
1.7).
MMRV vaccine safety in international studies – systemic reactions outcomes
• Randomized comparative study (Deichmann , 2015) of 947 healthy German and Italian
children aged ≥12 to <24 months randomly assigned the children to one of three vaccination
arms in a 2:1:1. Group 1 received one MMRV dose and one hexavalent vaccine concomitantly
at separate injection sites, group 2 recei ved MMRV only, and group 3 received the hexavalent
vaccine only. In the MMRV -only group (n=234), 61.1% (n=143) were reported to have a t least
one rectal (or equivalent) temperature ≥38 degrees Celsius within 0 -28 days following vaccination
(48 of those study participants were reported to have at least one rectal (or equivalent )
temperature ≥39.4 degrees Celsius) ; 1.3% (n=3) were reported to have irritability within 0 -28
days following vaccination; no participants were reported to have mumps/mumps- like illn ess
within 0 -28 days following vaccination.
• One prospective cohort from Italy (Cocchio , 2016) of 10395 healthy fourteen -month old
children eligible for their first vaccination against measles, mumps, rubella, and varicella
assessed adverse events relating to two different vaccination strategies: Priorix -Tetra
vaccination (n=5265) or separate MMR and varicella vaccination administered on the same day
(n=5130). The findings suggested a decreased risk of fever ≤ 39.4 degrees Celsius following
MMR + V compared to Priorix -Tetra [RR 0.58 (95% CI, 0.54 -0.63)]. This study reported no
difference in risk of fever ≥ 39.5 degrees Celsius following MMR + V compared to Priorix -Tetra
[RR 0.80 (95% CI , 0.69 -1.00)] , an increased risk of irritability following MMR + V compared to
MMRV* [RR 1.35 (95% CI, 1.21 -1.51)] , increased risk of parotid swelling following MMR + V
compared to Priorix -Tetra [RR 1.73 (95% CI, 1.02 -2.92)] , and an increased risk of arthralgia
following MMR + V compared to Priorix -Tetra [RR 1.82 (95% CI, 1.17 -2.82)] .
• Randomized comparative study (Haas , 2019) of 405 healthy French children aged 12 -18
months compared intramuscular (IM) and subcutaneous (SC) administration of two doses of MMRV given one month apart. In the 0 -28 days following the first MMRV dose administered by
IM route (n=202) or by SC route (n=203 ), vaccine -related pyrexia was reported in 35.6% (n=72)
and 39.4% (n=80) of recipients, respectively ; and mumps/mumps -like illness was reported in
the 0.5% (n=1) and 0% (n=0) of participants, respectively . In the 0 -28 days following the second
MMRV dose administered by IM route (n=201) or SC route (n=200), vaccine -related pyrexia
was reported in 16.9% (n=34) and 17% (n=34) of participants, respectively ; and
mumps/mumps -like illness was reported in the 0.5% (n=1) and 0% (n=0) of participants,
respectively .
Local reactions outcomes
There were no studies from the United States in this review that assessed local reactions
outcomes.
MMRV vaccine safety in international studies – pain outcome
• One prospective cohort from Italy (Cocchio , 2016) of 10395 healthy fourteen -month old
children eligible for their first vaccination against measles, mumps, rubella, and varicella
assessed adverse events relating to two different vaccination strategies: Priorix -Tetra
vaccination (n=5265) or separate MMR and varicella vaccination administered on the same day (n=5130). The findings suggested an increased risk of pain following MMR+V compared to
Priorix -Tetra [RR 3.33 (95% CI, 2.79 -3.98)].
• One randomized comparative study (Deichmann, 2015) of 947 healthy German and Italian
children aged ≥12 to <24 months randomly assigned the children to one of three vaccination
arms in a 2:1:1. Group 1 received one MMRV dose and one hexavalent vaccine concomitantly
at separate injection sites, group 2 received MMRV only, and group 3 received the hexavalent
vaccine only. In the MMRV -only group (n=234), 14.1% (n=33) were reported to have injection-
site pain within 0 -28 days following vaccination. owing vaccination in groups 1 and 3,
respectively .
MMRV vaccine safety in international studies – swelling outcome
• One prospective cohort from Italy (Cocchio , 2016) of 10395 healthy fourteen -month old
children eligible for their first vaccination against measles, mumps, rubella, and varicella assessed adverse events relating to two different vaccination strategies: Priorix -Tetra
vaccination (n=5265) or separate MMR and varicella vaccination administered on the same day
(n=5130). The findings suggested an increased risk of swelling following MMR + V compared
to Priorix -Tetra [RR 3.38 (95% CI, 2.45 -4.68)].
• One randomized comparative study (Deichmann, 2015) of 947 healthy German and Italian
children aged ≥12 to <24 months randomly assigned the children to one of three vaccination arms in a 2:1:1. Group 1 received one MMRV dose and one hexavalent vaccine concomitantly at separate injection sites, group 2 received MMRV only, and group 3 received the hexavalent
vaccine only. In the MMRV -only group (n=234), 2.6% (n=6) were reported to have injection -site
swelling within 0 -28 days following vaccination.
MMRV vaccine safety in international studies – redness outcome
• One prospective cohort from Italy (Cocchio , 2016) of 10395 healthy fourteen -month old
children eligible for their first vaccination against measles, mumps, rubella, and varicella
assessed adverse events relating to two different vaccination strategies: Priorix -Tetra
vaccination (n=5265) or separate MMR and varicella vaccination administered on the same day
(n=5130). The findings suggested an increased risk of redness following MMR + V compared
to Priorix -Tetra [RR 4.89 (95% CI, 3.73 -6.42)].
• One randomized comparative study (Deichmann, 2015) of 947 healthy German and Italian
children aged ≥12 to <24 months randomly assigned the children to one of three vaccination
arms in a 2:1:1. Group 1 received one MMRV dose and one hexavalent vaccine concomitantly at separate injection sites, group 2 received MMRV only, and group 3 received the hexavalent
vaccine only. In the MMRV -only group (n=234), 10.7% (n=25) were reported to have injection
site erythema within 0 -28 days following vaccination.
Hematologic al outcome
Immune thrombocytopenic purpura (ITP)
• A self -controlled case series (O’Leary, 20 11) with a cohort of 1.8 million children aged 6
weeks to 17 years within VSD identified a total of 197 chart- confirmed ITP cases. The analysis
indicated no significant elevated risk of ITP in MMRV recipients aged 12 -19 months within
the 1 - to 42 -day post -vaccination window (IRR 2.87 [95% CI, 0.78 -10.56].
Appendix
Table 3
Primary search strategy of MEDLINE (OVID), Embase (OVID), Cochrane Library CINAHL
(EBSCOHost),
DATABASE STRATEGY RUN DATE RECORD
COUNT
Medline
(OVID)
1946- 1. (Measles -Mumps -Rubella -Varicella OR chickenpox measles
mumps rubella vaccine OR MMRV OR ProQuad).mp
2. Exp Safety/ OR exp Treatment Outcome/ OR "Drug -Related
Side Effects and Adverse Reactions"/
3. (safety OR (vaccin* ADJ2 safe*) OR treatment outcome* OR
adverse* OR harm OR harmful OR harms OR side
effect*).ti,ab,kf. OR ae.fs
4. 2 OR 3
5. Exp Clinical Study/ OR exp Product Surveillance, Postmarketing/
6. (trial* OR observational stud* OR observation stud* OR
clinical stud* OR surveillance OR reporting system* OR VAERS OR postmarket* OR post -market*).ti,ab,kf,hw.
7. 5 OR 6
8. 1 AND 4 AND 7
9. Exp animals/ NOT exp humans/
10. 10 NOT 11
08/1/2025 111
Embase
(OVID)
1947- 1. chickenpox measles mumps rubella vaccine/
2. (Measles -Mumps -Rubella -Varicella OR chickenpox measles
mumps rubella vaccine OR MMRV OR ProQuad).ti,ab,kf.
3. 1 OR 2
4. Exp Safety/ OR exp Treatment Outcome/ OR adverse drug reaction/
5. (safety OR (vaccin* ADJ2 safe*) OR treatment outcome* OR adverse* OR harm OR harmful OR harms OR side effect*).ti,ab,kf. OR ae.fs
6. 4 OR 5
7. Exp Clinical Study/ OR exp Postmarketing Surveillance/
8. (trial* OR observational stud* OR observation stud* OR clinical stud* OR surveillance OR reporting system* OR VAERS OR postmarket* OR post -market*).ti,ab,kf,hw.
9. 7 OR 8
10. 3 AND 6 AND 9
11. Exp animal/ NOT exp human/
12. 10 NOT 11
13. limit 12 to "pubmed/medline" 08/1/2025 297
-
DUPLICATES
=200
UNIQUE
RECORDS
DATABASE STRATEGY RUN DATE RECORD
COUNT
14. 12 NOT 13
15. limit 14 to conference abstract status
16. 14 NOT 15
17.
Cochrane
Library
#1 (Measles -Mumps -Rubella -Varicella:ti,ab,kw OR “chickenpox
measles mumps rubella vaccine”:ti,ab,kw OR MMRV:ti,ab,kw
OR ProQuad:ti,ab,kw)
#2 [mh Safety] OR [mh "Treatment Outcome"]
#3 (safety:ti,ab,kw OR (vaccin*:ti,ab,kw NEAR/2 safe*:ti,ab,kw)
OR ("treatment" NEXT outcome*):ti,ab,kw OR adverse*:ti,ab,kw OR harm:ti,ab,kw OR harmful:ti,ab,kw OR
harms:ti,ab,kw OR ("side" NEXT effect*):ti,ab,kw)
#4 #2 OR #3
#5 [mh ^"Clinical Study"] OR [mh ^"Product Surveillance,
Postmarketing"]
#6 (trial*:ti,ab,kw OR ("observational" NEXT stud*):ti,ab,kw OR
("observation" NEXT stud*):ti,ab,kw OR ("clinical" NEXT stud*):ti,ab,kw OR surveillance:ti,ab,kw OR ("reporting" NEXT system*):ti,ab,kw OR VAERS:ti,ab,kw OR postmarket*:ti,ab,kw OR post -market*:t i,ab,kw)
#7 #5 OR #6
#8 #1 AND #4 AND #7
08/1/2025 54
-
DUPLICATES
=20
UNIQUE
RECORDS
CINAHL
(EBSCOHost) S1 (Measles -Mumps -Rubella -Varicella OR “chickenpox measles
mumps rubella vaccine” OR MMRV OR ProQuad)
S2 (MH Safety+) OR (MH "Treatment Outcomes+") OR (MH
"Adverse Drug Event+")
S3 ((TI safety OR AB safety OR SU safety) OR ((TI vaccin* OR AB
vaccin* OR SU vaccin*) N2 (TI safe* OR AB safe* OR SU safe*)) OR (TI "treatment outcome*" OR AB "treatment outcome*" OR SU "treatment outcome*") OR (TI adverse* OR AB adverse* OR SU adverse*) OR (TI harm OR AB harm OR SU
harm) OR (TI harmful OR AB harmful OR SU harmful) OR (TI
harms OR AB harms OR SU harms) OR (TI "side effect*" OR AB
"side effect*" OR SU "side effect*"))
S4 S2 OR S3
S5 (MH "Clinical Study+") OR (MH "Product Surveillance,
Postmarketing+") 08/1/2025 5
-
DUPLICATES
=3
UNIQUE RECORDS
DATABASE STRATEGY RUN DATE RECORD
COUNT
S6 ((TI trial* OR AB trial* OR SU trial*) OR (TI "observational
stud*" OR AB "observational stud*" OR SU "observational
stud*") OR (TI "observation stud*" OR AB "observation stud*" OR SU "observation stud*") OR (TI "clinical stud*" OR AB "clinical stud*" OR S U "clinical stud*") OR (TI surveillance OR
AB surveillance OR SU surveillance) OR (TI "reporting system*" OR AB "reporting system*" OR SU "reporting system*") OR (TI VAERS OR AB VAERS OR SU VAERS) OR (TI postmarket* OR AB postmarket* OR SU postmarket*) OR (TI post -market* OR AB
post -market* OR SU post -market*))
S7 S5 OR S6
S8 S1 AND S4 AND S7
S9 Limiters - Exclude MEDLINE records
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