Cambridge IGCSE Computer Studies 0420 — 2012 Oct/Nov Paper 3 · Variant 2

1 In this question you are asked to read about: • an existing system for appointments in a doctors' clinic; this is manual and paper- based; • the proposed replacement; this is to be a computer-based appointment system. You are given a description of both the existing and the proposed new computerised system. Description of the existing system The clinic has several doctors. When a patient wants to book an appointment with a doctor, the patient rings the doctors' receptionist. The receptionist asks for the following details: • patient name • first line of address • doctor requested The receptionist checks the files to ensure that the patient is registered with the clinic. The receptionist looks to find the requested doctor's free appointments in the appointments book. The receptionist offers the patient a day and a time for the appointment. If this is agreed then the patient's name is written in the space in the appointment book for that day and time. At the beginning of every day, the receptionist types an appointment list for each of the doctors for that day. The list contains the appointment times and patients’ names. When the patient arrives at the doctors' clinic for their appointment, they give their name to the receptionist. The receptionist informs each doctor as their patients arrive. Description of the proposed computer-based system The proposal is to replace all the paperwork. A computer-based appointment booking and arrival system will contain all the information described above. It will allow patients to book their appointments on a secure clinic website. On arrival at the clinic, the patient will be able to use a touch screen system to announce their arrival at the clinic. Each of the doctors and the receptionist will have a personal computer and a printer. There will be a personal computer with a touch screen for the patients to announce their arrival at the clinic. The computers and printers will be connected to a Local Area Network (LAN). In the new system, a patient will use a secure website to book an appointment with their doctor; they will only be able to book one appointment at any time. For patients to access the secure website the clinic will provide each patient with a code and the patient must choose a password. When the patient arrives at the clinic, they will use the touch screen to choose the answers to the following questions: • Choose male or female. • Choose the day of the month you were born on. • Choose the month you were born on. The system will use this information to identify the patient, the doctor and the time of the appointment. These details will be displayed on the screen and the patient will be asked to confirm their appointment. The system will then inform the doctor via their personal computer that the patient has arrived. A systems analyst is to be employed to review the existing manual method. The analyst will be responsible for drawing up an action plan for the new computer-based system. This will then be designed, built, tested and implemented. Technical and user documentation will be produced. Six months after the introduction of the new system, a full evaluation of its performance will be made. (a) The systems analyst has decided to use a Gantt chart and a PERT chart to ensure that the project is delivered on time. Explain what the following would be used for: (i) Gantt chart (ii) PERT chart [4] (b) Describe another software tool that the systems analyst could use to ensure that the project is delivered on time. [2] (c) Name two methods the analyst could use to gather information about the existing manual system. Explain how each method would be used to gather information about this manual system. Method 1 Explanation Method 2 Explanation [6]

Mark scheme: 1 (a) (i) up to three points from: - Gantt charts which show all stages/tasks to be done - Gantt charts which show key project milestones - number of days to do a task/complete project - progress of tasks as % complete - progress versus expected time to do work - how tasks are all linked together - Gantt charts allow deduction of critical path (ii) up to three points from: - PERT chart Project Evaluation and Review Technique - PERT charts show milestones (in their correct order) if not given in (i) - events are numbered sequentially - events are linked by activities - PERT charts show the critical path(s)/ shows shortest path for project completion (if not given in (i)) Max 4 points overall [4] (b) type of software one mark - project management software/spreadsheet description or example of use one mark e.g. - identifies tasks that must be completed on time - easy updating of Gantt or PERT charts etc. [2] (c) For each of two methods: one mark per method one mark for identifying how the method will be used for this case study one mark for a further explanation. Method - questionnaires Use - produce series of questions to give to patients/receptionists/doctors - no need for analyst to be present can leave questionnaires to be completed and collect later - responses can be anonymous etc. Method - interviewing/meetings Use - ask receptionists/doctors a number of face to face questions - allows questions to be tailored to the individual - allows follow up questions to be asked etc. IGCSE – October/November 2012 0420 32 Method - document search Use - gather information from documents/paperwork used in existing appointment booking system - allows procedures to be studied first hand - allows close scrutiny of all paperwork/files etc. Method - observation (not doctors) Use - watch receptionists doing their day to day tasks//patients arriving for their appointments - gives first hand knowledge of how system works etc. [6] (d) For each of two items: one mark per item of hardware one mark per reason why it would be needed Item - Network Interface Card Reason - to allow a computer to access the network Item - hub Reason - connects segments of a LAN Item - switch Reason - connects segments of a LAN (with reduced data collisions) Item - server Reason - various functions print, file etc. [4] (e) (i) up to four points - appropriate screen title - offered both male and female - confirm and try again - navigation buttons - clarity of instructions - good layout (ii) up to four points - appropriate screen title - offered all 31 days - can see all days of the month clearly If not given in (i) - confirm and try again - navigation buttons - clarity of instructions - good layout Max 4 per screen, 8 in total [8] IGCSE – October/November 2012 0420 32 (f) One mark for every two correct symbols A Process/operation B Disk storage C Keyboard/manual entry D Hard copy output E Sort F Input/output G Terminator/ Start and Stop H Connector 0, 1 - no marks 2, 3 - one mark 4, 5 - two marks 6, 7 - three marks 8 - four marks [4] (g) One mark per process, max 4 - Checking patient number and password - Selection of doctor - Offering appointment - Selection of appointment - Sorting and printing out/displaying list of appointments for a doctor One mark per input, max 2 - Patient Number - Password - Selection of Doctor - Selection of appointment time/date One mark per data store, max 2 - Patient file/database - Appointment file/database - Doctor file/database - Database (only if none of the above were given) One mark per output, max 2 - appointment (screen not paper) - lists for each doctor (screen or paper) [8] IGCSE – October/November 2012 0420 32 (h) Up to three points from: - advocate the use of strong passwords - encryption - use of firewall - vet employees (because of possibility of malpractice) - use of secure protocol e.g. HTTPS [3] (i) Up to three marks for reasons given (MUST match up with choice) Off-the-shelf software chosen for the following reasons: - appointment booking software readily available - already fully tested and de-bugged - usually less expensive to buy - technical support online/by phone - usually compatible with other existing software - community of knowledge available Bespoke software chosen for the following reasons: - can be tailored to meet the exact requirements of the doctors’ clinic - in contact with the actual programmers if there is a problem - software can develop as it is used - doesn’t contain unwanted features [3] (j) For each of three examples of test data: one mark per example one mark per reason, which must match example given - AB1234 - …this checks that system can accept appropriate inputs - AB12345 - …this checks that the data is the right length - 1234AB - …this checks that data has the right format [6] (k) For each of four items that should be included in technical documentation one mark per item one mark per reason - program listing/coding - …so alterations can be made - programming language(s) used - …so the application can be recompiled - flowchart/algorithm/pseudo-code - …so that the logic can be altered if required IGCSE – October/November 2012 0420 32 - System flowchart - …to give overview of whole system - Data Flow Diagram - …to show movement of data through the system - hardware requirements/ allow example such as memory requirement - …for testing any alterations - software requirements - …for testing any alterations - known “bugs” in the system - …so they can be removed - list of variables used (and their meaning/description)/data dictionary - …so that alterations don’t spawn new errors - file structures - …so that files and file sizes can be checked - sample runs/test plan/testing (with results and actual test data used) - …so that tests can be re-run when alterations are made - validation rules - …so that any extra inputs can be subject to similar validation - input/output formats - …so that any extra ones/alterations can follow the same format [8] (l) One mark for each of two methods One mark for each reason given to a maximum of two, which must match chosen method Direct changeover - no need to run 2 systems side by side - immediate benefits from new system - less disruptive for receptionists/doctors - more likely to work since it will have been fully tested first Parallel implementation - operate both systems together side by side - good for training receptionists/doctors since both systems can be compared - if new system fails have old manual system as a back up Pilot implementation - adopt new system at one clinic - can easily re-introduce old system if problems occur - makes sure system fully works before adopting at another clinic Phased implementation e.g. - part of system (e.g. patient arrivals) introduced initially for trials - if it is OK, gradually introduce other parts of the new system - if a problem occurs, can stop using it any stage - allows receptionists/doctors to gain confidence in its operation [4]