Studies

There are many types of evidence such as scientific, historical and experiential. Science, like all other types of evidence, has it's strengths as well as weaknesses. Studies can be strongly or poorly designed and influenced by bias or any number of motivations. Data can be cherry-picked and study conclusions do not always match the evidence within. Here are a few questions to ask when critically assessing a study and it's findings:

What type of study is it? A Meta-Analysis, a Randomized Controlled Trial, Cross-Over Study,, etc.
Who directly or indirectly funded the study?
Do the study headlines match the content?

Vaccination

The Unofficial Vaccine Educators: are CDC funded non-profits sufficiently independent?

Adverse events from drugs and vaccines are common, but underreported...fewer than 1% of vaccine adverse events are reported.

Infant mortality rates regressed against number of vaccine doses routinely given.

Evidence of Increase in Mortality After the Introduction of Diphtheria-Tetanus-Pertussis Vaccine to Children Aged 6-35 Months

Eczema Vaccinatum

Data demonstrates that maternal reactions following receipt of Tdap in pregnancy are common

Children who get the flu vaccine are more at risk for hospitalization than their peers who do not get the vaccine, especially asthmatic children.

Those vaccinated for the flu showed increased viral shedding compared to those not vaccinated, especially when vaccinated two years in a row

The available evidence for people aged 65 years or older with regard to the safety, efficacy or effectiveness of influenza vaccines is of poor quality and provides no guidance.

Tamiflu use could induce sudden deterioration leading to death, especially within 12 hours of prescription.

Flu vaccination not found to decrease incidence of influenza infection, but was associated with significantly increased risk of non influenza respiratory infections

Despite high levels of vaccination coverage, pertussis circulation cannot be controlled at all.

Immunocompromised contacts should be advised to avoid contact with stool from the Rotovirus immunised child if possible, particularly after the first vaccine dose for at least 14 days.

Acellular pertussis vaccines protect against disease but fail to prevent infection and transmission in a nonhuman primate model

Asymptomatic transmission is the most parsimonious explanation for many of the observations surrounding the resurgence of B. pertussis in the US and UK.

"Vaccinated adolescents and adults may serve as reservoirs for silent infection and become potential transmitters to unprotected infants (3-11). The whole-cell vaccine for pertussis is protective only against clinical disease, not against infection (15-17). Therefore, even young, recently vaccinated children may serve as reservoirs and potential transmitters of infection.”

"The apparent paradox is that as measles immunization rates rise to high levels in a population, measles becomes a disease of immunized persons."

Subtle DNA changes are connected to and the overuse of vaccines and consequentaly, autism.

Theoretical aspects of Autism: Causes—A review

Autism and resulting medical conditions

Mercury from Thimerosal-containing biologic/vaccine preparations may contribute to Autism Spectrum Disorder.

Mercury and Autism: accelerating evidence?

Elevated levels of measles antibodies are found in children with Autism.

Evidence suggests a strong association between MMR and CNS autoimmunity in Autism.

Tylenol, MMR and Autism - A parent survey study

A positive association is found between childhood vaccination uptake and Autism prevalence.

Increases in Autism and Cancer correspond with the introduction of vaccines using human fetal cell lines and retroviral contaminants.

Autism: a novel form of mercury poisoning

Conjugate vaccines (like that for Hib) may predispose children to autism spectrum disorders.

A two-phase study evaluating the relationship between Thimerosal-containing vaccine administration and the risk for an autism spectrum disorder diagnosis in the United States

Missing Evidence

Perhaps as significant as the growing body of vaccine critical research is the general lack of evidence coming from pro-vaccine sources that vaccines are safe and effective.

True placebos such as saline injections are rarely used in vaccine research. Sometimes a placebo is used in a "Cross-Over" study or combined with an aluminum "control" before publishing results; or the words "saline placebo" are otherwise used in a manner that muddles the general lack of honest control groups. One should always consider what constitutes the control group in order to relevantly assess the results of any study.
Headlines or conclusions of vaccine safety and effectiveness are often not substantiated by the evidence within a study but many professionals do not read these details. You, the consumer, still can.
Most vaccine safety studies do not actively follow participants for adverse events for more than a few days, so autoimmune issues and deaths and injuries caused by certain mechanisms would be missed.
Research widely considered by the mainstream to be "reputable" and "credible" fails to compare the vaccinated to the unvaccinated.
A study examining the synergistic effects of all vaccines recommended to be given at the same time by the CDC does not exist.