Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our User Agreement and Privacy Policy.

Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User Agreement for details.

Successfully reported this slideshow.

Like this presentation? Why not share!

- Introduction to Biostatistics by Abdul Wasay Baloch 1695 views
- Introduction to biostatistics by Ali Al Mousawi 5768 views
- Epidemiolgy and biostatistics notes by Charles Ntwale 463 views
- Introduction to biostatistics by o_devinyak 1027 views
- biostatistics basic by jjm medical college 1364 views
- 2014.06.19 Tomo Popovic Disertacija... by Tomo Popovic 578 views

1,215 views

Published on

No Downloads

Total views

1,215

On SlideShare

0

From Embeds

0

Number of Embeds

1

Shares

0

Downloads

39

Comments

0

Likes

4

No embeds

No notes for slide

- 1. الرحيم الرحمن ال بسمالرحيم الرحمن ال بسم
- 2. Introduction toIntroduction to BiostatisticsBiostatistics Dr. Moataza Mahmoud Abdel Wahab Lecturer of Biostatistics High Institute of Public Health University of Alexandria
- 3. BiostatisticsBiostatistics (a portmanteau word made from biology and statistics) The application of statistics to a wide range of topics in biology.
- 4. BiostatisticsBiostatistics It is the science which deals with development and application of the most appropriate methods for the: Collection of data. Presentation of the collected data. Analysis and interpretation of the results. Making decisions on the basis of such analysis
- 5. Other definitions for “Statistics” Frequently used in referral to recorded data Denotes characteristics calculated for a set of data : sample mean
- 6. Role of statisticians To guide the design of an experiment or survey prior to data collection To analyze data using proper statistical procedures and techniques To present and interpret the results to researchers and other decision makers
- 7. Sources of data Records Surveys Experiments Comprehensive Sample
- 8. Types of dataTypes of data Constan t Variable s
- 9. Quantitative continuous Types of variables Quantitative variables Qualitative variables Quantitative descrete Qualitative nominal Qualitative ordinal
- 10. Numerical presentationNumerical presentation Graphical presentationGraphical presentation Mathematical presentationMathematical presentation Methods of presentation of data
- 11. 1- Numerical presentation Tabular presentation (simple – complex) Simple frequency distribution Table (S.F.D.T.) Title Name of variableName of variable (Units of variable)(Units of variable) FrequencyFrequency %% -- - Categories- Categories -- TotalTotal
- 12. Table (I): Distribution of 50 patients at the surgical department of Alexandria hospital in May 2008 according to their ABO blood groups BloodBlood groupgroup FrequencyFrequency %% AA BB ABAB OO 1212 1818 55 1515 2424 3636 1010 3030 TotalTotal 5050 100100
- 13. Table (II): Distribution of 50 patients at the surgical department of Alexandria hospital in May 2008 according to their age AgeAge (years)(years) FrequencyFrequency %% 20-<3020-<30 30-30- 40-40- 50+50+ 1212 1818 55 1515 2424 3636 1010 3030 TotalTotal 5050 100100
- 14. Complex frequency distribution Table Table (III): Distribution of 20 lung cancer patients at the chest department of Alexandria hospital and 40 controls in May 2008 according to smoking Smoking Lung cancer Total Cases Control No. % No. % No. % Smoker 15 75% 8 20% 23 38.33 Non smoker 5 25% 32 80% 37 61.67 Total 20 100 40 100 60 100
- 15. Complex frequency distribution Table Table (IV): Distribution of 60 patients at the chest department of Alexandria hospital in May 2008 according to smoking & lung cancer Smoking Lung cancer Total positive negative No. % No. % No. % Smoker 15 65.2 8 34.8 23 100 Non smoker 5 13.5 32 86.5 37 100 Total 20 33.3 40 66.7 60 100
- 16. 2- Graphical presentation Graphs drawn using Cartesian coordinates • Line graph • Frequency polygon • Frequency curve • Histogram • Bar graph • Scatter plot Pie chart Statistical maps rules
- 17. Line Graph 0 10 20 30 40 50 60 1960 1970 1980 1990 2000 Year MMR/1000 Year MMR 1960 50 1970 45 1980 26 1990 15 2000 12 Figure (1): Maternal mortality rate of (country), 1960-2000
- 18. Frequency polygon Age (years) Sex Mid-point of intervalMales Female s 20 - 3 (12%) 2 (10%) (20+30) / 2 = 25 30 - 9 (36%) 6 (30%) (30+40) / 2 = 35 40- 7 (8%) 5 (25%) (40+50) / 2 = 45 50 - 4 (16%) 3 (15%) (50+60) / 2 = 55 60 - 70 2 (8%) 4 (20%) (60+70) / 2 = 65 Total 25(100%) 20(100%)
- 19. Frequency polygon Age Sex M-P M F 20- (12%) (10%) 25 30- (36%) (30%) 35 40- (8%) (25%) 45 50- (16%) (15%) 55 60-70 (8%) (20%) 65 0 5 10 15 20 25 30 35 40 25 35 45 55 65 Age % Males Females Figure (2): Distribution of 45 patients at (place) , in (time) by age and sex
- 20. 0 1 2 3 4 5 6 7 8 9 20- 30- 40- 50- 60-69 Age in years Frequency Female Male Frequency curve
- 21. HistogramHistogram 0 5 10 15 20 25 30 35 0 25 30 40 45 60 65 Age (years) % Figure (2): Distribution of 100 cholera patients at (place) , in (time) by age
- 22. Bar chart 0 5 10 15 20 25 30 35 40 45 % Single Married Divorced Widowed Marital status
- 23. Bar chart 0 10 20 30 40 50 % Single Married Divorced Widowed Marital status Male Female
- 24. Pie chart Deletion 3% Inversion 18% Translocation 79%
- 25. Doughnut chart Hospital A Hospital B DM IHD Renal
- 26. 3-Mathematical presentation Summery statistics Measures of locationMeasures of location 1- Measures of central tendency1- Measures of central tendency 2- Measures of non central locations2- Measures of non central locations (Quartiles, Percentiles )(Quartiles, Percentiles ) Measures of dispersionMeasures of dispersion
- 27. 1- Measures of central tendency (averages) MidrangeMidrange Smallest observation + Largest observationSmallest observation + Largest observation 22 ModeMode the value which occurs with the greatestthe value which occurs with the greatest frequencyfrequency i.e.i.e. the most common valuethe most common value Summery statistics
- 28. 1- Measures of central tendency (cont.) MedianMedian the observation which lies in the middle ofthe observation which lies in the middle of the ordered observation.the ordered observation. Arithmetic mean (mean)Arithmetic mean (mean) Sum of all observationsSum of all observations Number of observationsNumber of observations Summery statistics
- 29. Measures of dispersion RangeRange VarianceVariance Standard deviationStandard deviation Semi-interquartile rangeSemi-interquartile range Coefficient of variationCoefficient of variation ““Standard error”Standard error”
- 30. Standard deviation SD 7 7 7 7 7 7 7 8 7 7 7 6 3 2 7 8 13 9Mean = 7 SD=0 Mean = 7 SD=0.63 Mean = 7 SD=4.04
- 31. Standard error of mean SE A measure of variability among means of samples selected from certain population SE (Mean) =SE (Mean) = SS nn

No public clipboards found for this slide

Be the first to comment