Hajian-Tilaki K Sample size estimation in diagnostic test studies of biomedical informatics. J Biomed Inform. 2014 Apr;48:193-204. doi: 10.1016/j.jbi.2014.02.013. Epub 2014 Feb 26.
Kang SW, Bach JR Maximum insufflation capacity: vital capacity and cough flows in neuromuscular disease. Am J Phys Med Rehabil. 2000 May-Jun;79(3):222-7.
Lanig IS, Peterson WP The respiratory system in spinal cord injury. Phys Med Rehabil Clin N Am. 2000 Feb;11(1):29-43, vii. Review.
Liebscher T, Niedeggen A, Estel B, Seidl RO Airway complications in traumatic lower cervical spinal cord injury: A retrospective study. J Spinal Cord Med. 2015 Sep;38(5):607-14. doi: 10.1179/2045772314Y.0000000254. Epub 2014 Aug 12.
Mueller G, Hopman MT, Perret C Comparison of respiratory muscle training methods in individuals with motor and sensory complete tetraplegia: a randomized controlled trial. J Rehabil Med. 2013 Mar;45(3):248-53. doi: 10.2340/16501977-1097.
Postma K, Bussmann JB, Haisma JA, van der Woude LH, Bergen MP, Stam HJ Predicting respiratory infection one year after inpatient rehabilitation with pulmonary function measured at discharge in persons with spinal cord injury. J Rehabil Med. 2009 Sep;41(9):729-33. doi: 10.2340/16501977-0410.
Tollefsen E, Fondenes O Respiratory complications associated with spinal cord injury. Tidsskr Nor Laegeforen. 2012 May 15;132(9):1111-4. doi: 10.4045/tidsskr.10.0922. Review. English, Norwegian.
Wang AY, Jaeger RJ, Yarkony GM, Turba RM Cough in spinal cord injured patients: the relationship between motor level and peak expiratory flow. Spinal Cord. 1997 May;35(5):299-302.
Inspiratory Muscle Strength and Respiratory Complications After Spinal Cord Injury: a Multicenter, Prospective Cohort Study
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.