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Data Collection Tools and Creation of a Usable Database . Adam Schlichting University of Illinois at Chicago Department of Emergency Medicine. Last updated: 10.18.2002. Introduction Why?. DO NOT COPY INFORMATION DIRECTLY FROM CHARTS INTO A COMPUTER DATABASE! Decrease mistakes Lose charts
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Data Collection Tools and Creation of a Usable Database Adam Schlichting University of Illinois at Chicago Department of Emergency Medicine Last updated: 10.18.2002
IntroductionWhy? • DO NOT COPY INFORMATION DIRECTLY FROM CHARTS INTO A COMPUTER DATABASE! • Decrease mistakes • Lose charts • Concisely store all of the data for your study • Data sheets can be checked in seconds, charts take minutes to hours
IntroductionThe Questions • Before designing a data collection tool, you must have a clear answer to the following questions: • What is it you are trying to show with your study? • What is the main hypothesis? • What is the 2nd, 3rd, 4th, hypothesis? • What data will you need to form your conclusion? • Think about your final manuscript and work backwards • Use your abstract as a template
IntroductionThe Balancing Act • Collecting data is time consuming • Collect only what you need • Going back to collect more data later is painful • Collect ALL the data you need for each case
Data Collection ToolThe Fields • What information do you need for every case? • Trackable case ID • Allows you to find case again • MR# • Study ID# • Date • Demographic information (who you studied) • Sex • Age • Race/ethnicity
Data Collection ToolThe Fields • If multiple investigators/sites: • Who recorded the case (initials)? • Which site? • Specify formats: • Time: 24 hour time or AM/PM? • Dates: July 4, 1987 • 04.07.87 (European) • 07.04.87 (U.S.)
Data Collection ToolSimplify and Specify Data Collection • Circle or check-boxes • Forces conformity on data recorders • Reduces problems caused by illegibility • Include all possible selections that may be of interest • Include “Other”/”Other Specify” • How many choices should be selected? • All that apply? • Most pertinent? • Most severe?
Data Collection ToolExamples • Chest Pain • Prospective with chart review component • Violence in EMS • Anonymous, cross-sectional survey • No specific identifying information
Data Collection ToolStoring • Once you have begun collecting data, make copies • Keep a reserve, off-site copy of all of your work • Don’t store it in your car
Creating a DatabaseWhy? • Once you have collected your data: • Pile of paper with information • To draw any conclusions from these data • Analyze en-mass • Analyze many variables • Analyze relationships between variables
Creating a DatabaseGeneral Tips • Make it simple but complete • Incorporate all info used at the beginning: Demographics (age, sex, race….), hypothesis questions, inclusion and exclusion questions, outcomes • No chances to go back and recollect data once the study is over • Make it yes/no as much as possible • Easiest to enter data on a spreadsheet when 1=yes and 2=no
Creating a DatabaseGeneral Tips • Data sheets should have a logical flow • Needs to make sense to people not directly involved in the study • Provide a way of accounting for data sheets (i.e. subjects) • Numbering system works best • Remember to maintain subject confidentiality • Make data sheet simple if subject needs to fill it out • Use lay terms, not medical terms
Creating a DatabaseGeneral Tips • Opening paragraph at the top of each data sheet that provides an explanation of the project • Use language appropriate to reader • If appropriate, have a second sheet that includes reference phone numbers • Subject may call these numbers if he or she has any questions • Spell check your work!
Creating a DatabaseWhat To Use • Microsoft Excel • Easy to use • Microsoft Access • More difficult to setup • Once constructed, more difficult to screw-up • D-BASE • We’ll focus on Excel
Creating a DatabaseMicrosoft Excel • Rows • Columns
Creating a DatabaseMicrosoft Excel • 1 case = 1 row • Each variable for that case goes in a separate column • Label column using first row only • Variable labels may be up to 8 characters long (for analysis)
Creating a DatabaseMicrosoft Excel: Encoding Variables • Use a blank data collection tool as a decoder • KEEP MULTIPLE COPIES OF THIS DECODER SHEET
Creating a DatabaseMicrosoft Excel: Encoding Variables • Can enter numbers or text • Male / Female • M / F • 1 / 0 ***** • 1 / 2 • During later analysis • Can do frequency counts on text variables • Can’t do regressions using text variables
Creating a DatabaseMicrosoft Excel: Encoding Variables • For simplicity, use M / F • Should you need to do regressions, recoding variables later to 1 / 0 is not difficult
Creating a DatabaseMicrosoft Excel: Encoding Variables • Date / Time • Separate columns for month, date, year • Can merge later • Separate columns for hours, minutes • Can merge later
Creating a DatabaseMicrosoft Excel: Encoding Variables • Multiple choice questions • 1: choice one • 2: choice two • 3: choice 3 • … • No data • Leave blank: excluded from freq. counts • 99: how many cases had missing data
Creating a DatabaseMicrosoft Excel: Encoding Variables • Multiple choice questions with ‘other’ • Create variable for ‘specify if other’ • Input text • If no data, leave blank
Creating a DatabaseMicrosoft Excel: Encoding Variables • Free response questions • Age: _________ • Blood Pressure: _________ • Divide into DBP and SBP • If no data, leave it blank
Creating a DatabaseMicrosoft Excel: Encoding Variables • Free response questions • Age: _________ • Blood Pressure: _________ • Divide into DBP and SBP • If no data, leave it blank
Creating a DatabaseMicrosoft Excel: Save Early and Often • Save in multiple locations • Keep a copy for yourself • Harddrives crash • Keep a copy on floppy disk