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Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 1
Practical Data Collection
Medical ElectivesData Collection
The Practical Aspects
John S. Lemon
IT Services
Practical Data Collection
Preparation – the 5 ‘P’s• Poor Preparation Produces Poor
Performance
or
Prior Preparation Produces Perfect Products
• Applies to ALL aspects of the elective–Including collecting and analysing your
data.
Practical Data Collection
Relevance of Data Collection• “What bearing do these pictures have
on your elective ?”
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 2
Practical Data Collection
Previous Electives• All places where
previous electives have taken place–Sunburn / skin
cancer on Bondi beach
–Altitude sickness in La Paz, Bolivia
–Medical provision in Nepal / Annapurna
Practical Data Collection
Previous Electives• Not everywhere provides the same as
Aberdeen
Practical Data Collection
Which facilities would you expect at each place ?
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 3
Practical Data Collection
Which do you actually get ?
What 2 students found
Laptops / wireless hotspots and internet cafes almost everywhere – BUT -
Practical Data Collection
Facilities for Data Collection• Don’t always assume that the facilities
will be similar to Aberdeen for:–Hardware–Software
• Extremely variable• May cost you to use
–Internet cafes –Wireless hotspots–University facilities–Laptop
Practical Data Collection
Laptop• Problems / limitations
–Security – theft–Climate – heat / dust / humidity–Power – reliable
• 1 hr / day in some places –Software – licenced for use
• Compatibility with ‘remote’ facilities
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 4
Practical Data Collection
Software• Always adopt the KISS technique
–Keep It Supremely Simple• But always use the best tool for the job
Practical Data Collection
Software• Questionnaires
–SNAP not Word• Storing data
–SPSS not Access–Perhaps Excel if no access to SPSS
• Statistics and Charts–SPSS not Excel
• In ALL cases learn early BEFORE you go away / start writing up
Practical Data Collection
Writing up• Make sure you have access to Word
–or some form of wordprocessor• Prepare as much as possible before
leaving Aberdeen–References – use Refworks –Produce outline, Introduction and
literature review• Do NOT leave until last minute.
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 5
Practical Data Collection
Timings• Avoid the ‘traditional’ student approach
of:lastminute.com
• It seldom works• Do NOT
–Fly back from New Zealand on Thursday when you submit on Monday
–Start to learn SPSS / SNAP/ Refworks two days before flying to Vanuatu
–Expect anyone to drop everything for you
Practical Data Collection
Possible solutions• Get a laptop and install the right
software–Student versions of Microsoft Office–SPSS - site licence for staff and students
• Create questionnaire in SNAP:–Collect on paper and type into laptop–Type data into web version from abroad
Practical Data Collection
What should you do ?• Plan early:
–Travel - to allow for submission on time• writing up takes longer than you think
–Determine what computing facilities you will / may have access to
• Seek help on how to collect, store and analyse your data
• Ask people who have experience of assisting with projects
• NOT ‘friends’
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 6
Practical Data Collection
Why so much Data ‘stuff’ ?
“Deciding on how to store your data or consulting a statistician** after the data has been collected is like hiring a physician for a patient who is in the morgue. He may be able to tell you what went wrong, but he is unlikely to be able to fix it”
**Decide on analysis before collecting data.
Practical Data Collection
Two areas to consider• Data Handling - an overview
–Glossary of terms–Quantity, Structure, Storage etc
• Data Handling systems–Which system suits which application
• Use the proper tools for the job ‘Horses for courses’
Practical Data Collection
Glossary of Terms • Different names for collections of data• Components of collections of data -
what makes up a data set• Software types - the names for what
does what !
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 7
Practical Data Collection
Glossary of Terms • The components of collections of data
are -Column Variable Observation
Row Cell Value Data Item
Case Value Data Item Cell
Record Data Item Cell Value
Collections of data - can be called Matrix File Table
Practical Data Collection
Glossary of Terms • A related set of tables / matrices may
be called–Data base–Data bank
Does NOT mean that to handle data you need a
Data Base Management System ( DBMS )
such as Access
Practical Data Collection
Software types • Types to be discussed -
–Word processors–Spreadsheets–Data base management systems–Statistical packages
• An overall description which outlines -–Functionality –Strengths and weaknesses
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 8
Practical Data Collection
Software - Word Processors• Designed for the specific purpose of
text handling• NOT for storing data except to
present as a document ( i.e. a data ‘display’ tool )
Practical Data Collection
Software - Spreadsheets • Essentially computer manipulated grids• A ‘general purpose tool’
–easy data entry–powerful computation facilities–data storage–data manipulation
• limited to sorting and crude subsetting
• Statistical functionalityVery SUSPECT
Practical Data Collection
Software – Data Base Management Systems
• Basically a way of ‘linking’ two or more‘spreadsheets’ / tables / matrices
–almost unlimited data storage–powerful data manipulation including
• subsetting• sorting
• Too powerful for most users and application
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 9
Practical Data Collection
Software - Statistical packages • Typically ‘spreadsheet like’ appearance• Designed for statistical analysis• Usually have powerful data
manipulation• Charting and graphing facilities• Presentation quality output which can
be easily incorporated into word processed documents
• Some may produce Web pages directly
Practical Data Collection
Glossary & Software types • Not an exhaustive glossary but
sufficient for this part of the lecture• Now move on to aspects of Data
Handling in general
Practical Data Collection
Six Key Areas• Structure• Quantity• Source• Type• Storage• Analysis
MUST consider as a WHOLE –NOT individually
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 10
Practical Data Collection
• Structure• Quantity• Source• Type• Storage• Analysis
Cannot omit ANY aspect without problems
Six Key Areas
Practical Data Collection
Six Key Areas - Structure• Structure• Quantity• Source• Type• Storage• Analysis
Practical Data Collection
Structure - Simple / Related• Simple rectangular Matrix - most common
form– questionnaire– lab or field work measurements
• Related matrices– two or more rectangular matrices linked by
common data items– eg. “University experience” survey - 1st, 2nd,
3rd, Final yearCommon item(s)- Matriculation Number- Age, sex, place of birth, degree
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 11
Practical Data Collection
Structure within data sets
• Repeating variables– common mistake to set out in this format– can cause problems in analysis
• SPSS may be able to ‘correct’ wrong layout• but - NOT guaranteed
North East South West Species Season51 34 25 27 Oak Spring
42 31 20 22 Oak Summer
43 33 20 21 Oak Autumn
49 37 22 24 Oak Winter
58 42 28 30 Beech Spring
53 39 25 27 Beech Summer
Practical Data Collection
Structure within data sets
• Repeating cases– more flexible– easily analysed– may be only format /
structure that can beanalysed
– initially seems to involve more data entry
• BUT – may save time
Season Species Location Lichen
Spring Oak North 51
Spring Oak East 34
Spring Oak West 25
Spring Oak South 27
Summer Oak North 42
Summer Oak East 31
Summer Oak West 20
Summer Oak South 22
Autumn Oak North 43
Autumn Oak East 33
Autumn Oak West 20
Autumn Oak South 21
Winter Oak North 49
Winter Oak East 37
Winter Oak West 22
Winter Oak South 24
Spring Beech North 58
Spring Beech East 42
Spring Beech West 28
Spring Beech South 30
Summer Beech North 53
Summer Beech East 39
Summer Beech West 25
Summer Beech South 27
Practical Data Collection
Six Key Areas - Quantity• Structure• Quantity• Source• Type• Storage• Analysis
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 12
Practical Data Collection
Quantity - Simple• Rectangular matrix
Cells = Columns x RowsCells = Questions x Respondents
–Long narrow matrices GOOD• Few columns / measurements Many rows /
cases
–Wide short matrices BAD• Many columns Few rows
Practical Data Collection
Quantity – how many cases ?• Are there enough patients / cases ?• Prospective
–In your 6 weeks data collection will there be enough ?
–e.g – how many cases of obstetric coleostatis per year ?
• Retrospective –Get more cases but has:
• Protocol changed• Staffing levels etc.
Practical Data Collection
Quantity – how many cases ?• For electives use the “Rule of four”• You need a minimum of 4 cases /
rows per column• 20 questions = 80 cases / patients• Remember
–Long and Narrow–NOT short and fat
• Must calculate at every stage in design and execution of a project
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 13
Practical Data Collection
Quantity - Data entry• How
–Keyboard–Optical Mark / Character Reader (scanner) –?
• Who–You –?
• Keystrokes 100 = 4 keystrokes
Practical Data Collection
Quantity - Related data• ‘To collect or not to collect’
‘That is the question’‘Whether you collect all you can’‘Or discard the irrelevant’
• Will it enhance or subtract from the study• Effect on the ‘shape’ of the data• For example - do you need these items ?
– Age, Sex, Place of Residence, Marital Status etc.• Remember 4 more cases per extra item / column
– Weather data
Practical Data Collection
Six Key Areas - Source• Structure• Quantity• Source• Type• Storage• Analysis
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 14
Practical Data Collection
Source – existing records
• Transfer to your system for analysis• Paper – you have to transfer carefully to
avoid transcription errors.• Export from computer system
– Format– Relevance– Permissions / ethics– Who does it and when
Practical Data Collection
Source – Questionnaires**
• Simple– single response questions
** Believed to be an easy option – but it isn’t to do it right !!
Practical Data Collection
Multiple Choice• Single question with more than one
response
Actually Eight separate questions
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 15
Practical Data Collection
Response Grids• Typical questions show little thought
• Couch potatoes 1 Eager beavers 5+
Practical Data Collection
Response grids• Alphabetic list caused problems
–Aerobics – Athletics – Ballet – Brownies -.. - Walking
• Revised question shows more thought and an effective pilot
Practical Data Collection
Six Key Areas - Type• Structure• Quantity• Source• Type• Storage• Analysis
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 16
Practical Data Collection
Type - numeric• Integer - whole numbers
– 1 -15 237 -1,297,428• Real - decimal point
– 0.19 -2.7 200.45 -1,435,276.783• Date / Time
31 12 2006 not 31 12 0610:00 AM or 23:33:00
• ensure software allows calculations ( e.g. days difference between one date and
another )
Practical Data Collection
Type - String / Character• String - Categorical
Y = ‘Yes’ cf. 1 ( or 2 )AB = ‘Blood group AB’ 5AB155 ‘West End of Aberdeen’
• String - Free text“To be or not to be,Whether ‘tis nobler in the mind,To suffer the strings and arrows .....”
University Office, Regent Walk, ABERDEEN
Practical Data Collection
Type - Other• Qualitative
‘Please state what you thought of ....’‘Other - please specify’
• Use ‘Other please specify’ with care !!
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 17
Practical Data Collection
Six Key Areas - Storage• Structure• Quantity• Source• Type• Storage• Analysis
Practical Data Collection
Storage - choices• Paper
vs.– ideal for small
studies – requires no
facilities–minimal learning
to get started
• Computer– few restrictions
on size –high Initial level
of learning–software Capacity–hardware
Capacity–cost– transferability
Practical Data Collection
Six Key Areas• Structure• Quantity• Source• Type• Storage• Analysis
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 18
Practical Data Collection
Analysis - Choices• Paper / Hand
vs– small studies– minimal
learning
• Computer– involves a high initial level of
learning• Software and hardware
must be -– simple to use– widely recognised– have good Support available
• Spreadsheet NO• Statistical package YES
Practical Data Collection
Analysis - Preliminary steps• Explore data before proceeding further• Basic statistics
–Min / Max / Means continuous data
Descriptive Statistics
891 11.16 56.06 22.5974 5.09680
1068 17 65 27.24 10.569
870
Body Mass IndexAge of respondent
(years)Valid N (listwise)
N Minimum Maximum Mean Std. Deviation
Practical Data Collection
Analysis - Preliminary steps• Explore data before proceeding further• Basic statistics
–Frequencies discrete data
Sex of respondent
643 58.4 59.2 59.2443 40.2 40.8 100.0
1086 98.6 100.015 1.4
1101 100.0
FemaleMale
Total
Valid
SystemMissingTotal
Frequency Percent Valid PercentCumulative
Percent
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 19
Practical Data Collection
Analysis - Preliminary steps• Explore data before proceeding further• Basic statistics
–Crosstabulation - 2 way tables discrete data
Sex of respondent * Age of Respondent (grouped) Crosstabulation
Count
194 277 70 55 29 3 628102 217 56 20 25 9 429296 494 126 75 54 12 1057
FemaleMale
Sex of respondent
Total
Under 20 21 - 30 31 - 40 41 - 50 51 - 60 Over 60Age of Respondent (grouped)
Total
Practical Data Collection
Analysis - Preliminary steps• Explore data before proceeding
further• Basic statistics
–Means / Max / Min within subgroupsboth
Report
22.0400 26.94507 628
4.91115 10.30123.3391 27.68
373 4295.29771 10.94722.5907 27.24
880 10575.11612 10.569
MeanNStd. DeviationMeanNStd. DeviationMeanNStd. Deviation
Sex of respondentFemale
Male
Total
Body MassIndex
Age ofrespondent
(years)
Practical Data Collection
Analysis - safe working method
• Check for integrity of data to exclude -–pregnant males–10 year old pensioners
• You may think your data is correct - BUT –
• In 99.9% of cases it ISN’T !!!
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 20
Practical Data Collection
Analysis - safe working method
• Correct any invalid data items• Run checks again to search for items missed
/ masked by previous errors• Repeat previous two steps until OK
– NB. You may get rid of the 10 year old pensioner but leave the 16 year old !!
• Only when no suspect data items can the analysis be performed
• The checking process CANNOT be neglected
Practical Data Collection
Summary• Think constantly about
– Structure ( Shape )– Quantity ( Size )– Source( From )– Type ( What )– Storage ( Where )– Analysis ( How )
If you do not consider the six key areas at ALL stages you risk the chance of failure
Practical Data Collection
The two areas to consider• Data Handling - an overview
–glossary of terms–Quantity, Structure, Storage etc
Data Handling systems which system suits which application the wrong choice can cost
–time - to restart the project–money - in labour costs, training and software
purchase
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 21
Practical Data Collection
How to choose - basic rules• Best way to illustrate is to use examples• This is not a definitive or exhaustive list• Seek advice as every application is different • Do not rely on ‘friends’• Remember - use the right tools for the job
Would you plough a field with a racehorse ?
Practical Data Collection
The choices - software names / types
• Software names referring to types–Access relational data base
management system (rDBMS)–Word Word processor–Excel Spreadsheet
• Most people use Microsoft Office and are unaware of alternatives–Star or Open Office Free – but …..
Practical Data Collection
The choices - software names / types
• Software names referring to specifics–SPSS Statistical package
• There are other statistical packages available but there may well be:–NO local support–NO local purchasing agreements for
discounts–So could end up being very expensive
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 22
Practical Data Collection
Bibliographic / reference managers
• References are data• Can manage by hand but a lot of work• Collect and store from day 1 of project • Must store and present references
correctly• Three approaches
–Buy PC based software ( Procite, Endnote etc. )
–Refworks web-based
Practical Data Collection
Bibliographic / reference managers
• Specialist software e.g. Reference Manager– Designed for the task– Provides the tools required for handling
references– Initial cost is high but offset by savings in time
and effort incurred trying to use the wrong tool !!
• Refworks – web based
Practical Data Collection
Access - relational system• Multiple linked tables
e.g. Student - course - lecturer• Powerful reporting and querying facilities• Appears easy to use – ‘friends’
recommendation's• Part of Microsoft Office / “everyone uses it”
- so must be good ( Is this really true ? )• Many hospitals / researchers use it for the
reasons above• Power and features are potential causes for
disasters
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 23
Practical Data Collection
Why is power potential for disaster ?
• Few software packages will warn of stupid or inconsistent actions
• Access like any relational system has many hidden features
• A relational system is like an icebergA lot is hiddenready to strike
when you least expect it.
Practical Data Collection
Questionnaire research - SPSS• SPSS - statistical package ( for analysis )
– designed and developed for this task– fairly intelligible output– can produce ‘presentation quality output’– used and supported world wide– reputation built on quality and reliability
Beware of ‘friends’ recommendations or ‘free’ software downloaded from Web
Practical Data Collection
SPSS
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 24
Practical Data Collection
Questionnaire design - SNAP• One integrated step from Q to A• Creates questionnaires ( Questions )• Collects the data
–paper–scanner–WWW
• Perform the analysis ( Answers )
Practical Data Collection
Why use SNAP instead of .... ?• Designing questionnaires with WORD• Storing and analysing the data with -
Excel - BADSPSS - Better
• Not designed for the whole job• Inflexible and not integrated
–cannot re-order questions easily–need to re-define data for the analysis
package
Practical Data Collection
Why use SNAP instead of .... ?Q 5 W h a t i s y o u r a r e a o f s t u d y
Ar ts & S o c i a lSc iences. .. .. ... .. ... .. .. ..
Educat ion . .. ... .. ... .. .. ..
E n g i n e e r i n g . ... .. .. ... .. .
Div in i ty .. .. ... .. ... .. .. ... .. .
L a w ... .. ... .. ... .. .. ... .. ... ..
Life Sc iences .. ... .. ... ..
Medic ine ... .. ... .. ... .. .. ..
Sc iences ... .. ... .. ... .. .. ..
Q 6 D o y o u h a v e y o u r o w n c o m p u t e r a t u n i v e r s i t y ?
Yes .. .. ... .. .. ... .. . N o. .. .. ... .. ... .. ... .
Q 7 D o y o u h a v e I n t e r n e t a c c e s s o n y o u r o w n c o m p u t e r ?
Yes .. .. ... .. .. ... .. . N o. .. .. ... .. ... .. ... .
Q 8 W h a t i s t h e s t a t e o f y o u r h e a l t h ?
VeryGood . ... .. ..
G o o d .. .. ... . N e i t h e rGood n o r
Bad .. ... .. .. .
Bad ... .. ... .. Very Bad .. C a n ' tc h o o s e . ... .
Section 2 - ( General questions about NHS )
Q 9 W h i c h o n e o f t h e s e s e r v i c e s p r o v i d e d b y t h e N H S h a v e y o u h e a r d o f ?
NHS DIRECT / N H S24 (Phone L i n e ) .. .. .. ..
N H S W A L K I NCL IN IC .. .. ... .. ... .. .. ... .. .
N H S n e t . .. ... .. .. ... .. ... .. Onl ine appo in tmen tserv ice .. ... .. ... .. ... .. .. ..
Q 1 0 H o w o f t e n h a v e y o u u s e d a n y s e r v i c e p r o v i d e d b y t h e N H S i n t h e p a s t y e a r ?
0 . .. ... .. ... .. .. ... .. . 1-3 .. .. ... .. ... .. ... . 4 - 7 . ... .. .. ... .. ... .. 8-10 . .. ... .. ... .. .. . More t han 1 0t imes ... .. ... .. ... .
Q 1 1 N H S a n d G e n e r a l P r a c t i c e d o c t o r s
Do you h a v e a genera l p rac t i t i one r that you p r e f e r to see i f y o u
h a v e to v is i t the doctor
Yes No Not Sure
Do you f e e l you h a v e loyalty towards you r own regu la r pract i t ioner
Do you h a v e conf idence in the serv ices prov ided by you r generalpract i t ioner
W o u l d you say you f e e l that you t rust you r genera l p rac t i t i oner
W o u l d you say you fe l t ' loyalty ' t owards the N H S
Do you f e e l that the N H S i s a loyal serv ice
Do you h a v e conf idence in the serv ices prov ided by the N H S
Section 3 - NHS DIRECT / NHS 24
NHS Direct/24 is a new 24-hour service telephone advice line staffed by nurse. It was established toprovide easier and faster information for people about health, illness and help themselves and their
families.
Q 1 2 H a v e y o u e v e r u s e d t h i s s e r v i c e ?
Yes .. .. ... .. .. ... .. . N o. .. .. ... .. ... .. ... .
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 25
Practical Data Collection
SNAP - integrated package
Practical Data Collection
SNAP - other advantages ?• WYSIWYG questionnaire design• Default styles, layouts and templates• Results can be displayed in many
different formats–tables–charts–as numbers on questionnaires
• Direct creation of SPSS files for further analysis
Practical Data Collection
SNAP - Percentages or counts
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 26
Practical Data Collection
SNAP - Charts
Practical Data Collection
SNAP - switch between views
Practical Data Collection
SNAP - difficult to use ?• A little more difficult than Word• Not as hard as Access• Perhaps the same as PowerPoint• Some commands are SNAP specific but
that is only to be expected• Latest version has many improvements
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 27
Practical Data Collection
Which would you use for ?1) Commuting within Aberdeen
2) Building a motorway
3) Formula 1 racing at Silverstone(a) (b) (c)
Practical Data Collection
The changing times - hardware
1978 - New university machineCost £1.5 millionRoom Tennis court size - air conditionedSupport Engineers, systems staff ( 10+ )
3 shifts of 4 operatorsSoftware Fortran, Cobol, IDS/II - batch mode Specification - 16 Mbytes RAM, 486 processor
3.2 GBytes disk1998 - equivalent
£150 ( a second hand laptop )2013 – iPhone or iPad – far more capacity !!
Practical Data Collection
The changing times - software• 1978 –
– Mainly user programmes written in• Algol• Fortran• System code / Assembler
– Batch compilations and execution sometimes taking hours
– Very few Packages• 2013
– No programming / Apps– Windows / GUI / ‘point and click’ / touch screen– ‘Instant’ results
Electives Talk from IT Services Tuesday, 14 May 2013
MBChB 28
Practical Data Collection
What if ??• If transport had changed at the same
rate as computing• No steering wheel, gearchange, brakes
etc.• Just display a map, click on it and• Fly there !!!
• Think of the chaos !!!
Practical Data Collection
John S. Lemon
Edward Wright BuildingDunbar Street
Aberdeen01224 273350 or (76)3350
j.s.lemon@abdn.ac.uk
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