23 biostat_lecture_1.pdf

Community Health Medicine Biostatistics Module Chunfa Jie, PhD [email protected] E4432 Edge of Innovation Des Moines University Course objectives Differentiate between different types of data, variables, measurement scales and sampling schemes Define and compute th...

Community Health Medicine Biostatistics Module Chunfa Jie, PhD [email protected] E4432 Edge of Innovation Des Moines University Course objectives Differentiate between different types of data, variables, measurement scales and sampling schemes Define and compute the measures of center and variability, and interpret basic graphical data presentations Interpret the direction and strength of linear correlation coefficient Understand the difference between descriptive and inferential statistics Comprehend the concepts of estimation and hypothesis testing Differentiate between the research hypothesis and the statistical hypotheses (Null and Alternative) Identify the components of statistical hypothesis testing, including null and alternative hypotheses, significance level, test statistic, p-value, decision making rule and interpretation Differentiate between point estimation and interval estimation, and understand confidence levels and margin of error Is it what you had in mind when you decided to pursue a career in medicine? Why do clinicians need to learn statistics? General goal: Get a solid grounding by learning the key statistics concepts Real Case Study: The Journal of Foot & Ankle Surgery 53 (2014) 29–31 Contents lists available at ScienceDirect The Journal of Foot & Ankle Surgery journal homepage: www.jfas.org Reduction of Intermetatarsal Angle after First Metatarsophalangeal Joint Arthrodesis in Patients with Hallux Valgus Mindi Feilmeier, DPM, FACFAS 1, Paul Dayton, DPM, FACFAS 2, 3, Jeffery C. Wienke Jr., DPM, AACFAS 4 1 Assistant Professor, Des Moines University College of Podiatric Medicine and Surgery, Des Moines, IA 2 Director, Podiatric Surgical Residency, Trinity Regional Medical Center, Fort Dodge, IA 3 Adjunct Professor, Des Moines University College of Podiatric Medicine and Surgery, Fort Dodge, IA The study was to observe the reduction of the IMA (Intermetatarsal 4 Podiatric Surgeon, Sanford Vascular Associates, Sanford Health, Sioux Falls, SD Angle when first MTPJ (Metatarsophalangeal Joint) Fusion was a r t i c l e i n f o Level of Clinical Evidence: 4 a b s t r a c t We present a radiographic review of 94 patients who underwent first metatarsophalangeal joint arthrodesis. performed in patients with first IMAs. Keywords: first metatarsophalangeal joint The main focus of our review was to assess the change in the intermetatarsal angle (IMA). The change in the IMA was measured for the entire group and for 2 subgroups (IMA 11! to 15! and IMA >15! ). The results of the angular measurements for the total data set were as follows: mean preoperative first IMA, 15.32! (range 11! to fusion hallux valgus 24! ), mean postoperative IMA, 9.88! (range 3! to 18! ), and mean change in IMA of 5.44! (range "2! to 13! ; intermetatarsal angle p <.001). Group 1, with an IMA of 11! to 15! , included 52 patients, with a mean change in the IMA of 4.21! reduction (range "2! to 9! ; p <.001). Group 2, with an IMA greater than 15! (range 16! to 24! ), included 42 patients, No problem understanding the finding below stated near end of with a mean change in the IMA of 6.83! (range 2! to 13! ; p <.001). The change in the preoperative to postoperative IMA in group 1 compared with that in group 2 was statistically significant (p <.001). The results of the present study have confirmed the observations of previous investigators that arthrodesis of the first the abstract: metatarsophalangeal joint for hallux abducto valgus deformity results in a reduction of the IMA and that a proportionately larger reduction can be expected when the IMA is larger. ! 2014 by the American College of Foot and Ankle Surgeons. All rights reserved. “The change in the preoperative to postoperative IMA in group 1 compared with that in group 2 was statistically significant (p