Gautam A, Mittal N, Singh TB, Srivastava R, Verma PK Correlation of ABO Blood Group Phenotype and Rhesus Factor with Periodontal Disease: An Observational Study. Contemp Clin Dent. 2017 Apr-Jun;8(2):253-258. doi: 10.4103/ccd.ccd_307_17.
Pai GP, Dayakar MM, Shaila M, Dayakar A Correlation between "ABO" blood group phenotypes and periodontal disease: Prevalence in south Kanara district, Karnataka state, India. J Indian Soc Periodontol. 2012 Oct;16(4):519-23. doi: 10.4103/0972-124X.106892.
Yu Q, Wang L, Zhang S, Feng T, Li L, Chen B, Chen M The role of ABO blood groups in Crohn's disease and in monitoring response to infliximab treatment. Blood Transfus. 2016 Sep;14(5):460-4. doi: 10.2450/2016.0199-15. Epub 2016 Feb 24.
Investigating the Role of ABO Blood Group in the Response to the Nonsurgical Periodontal Treatment.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
