Question 5 of 8: Function-Point Size and Cost Estimate for the Patient Registration System

Question 5: Function-Point Size and Cost Estimate for the Patient Registration System (20 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

Given. The Question-4 patient registration system: outpatient registration/scheduling, inpatient registration/bed allocation, and department dispatch. The IFPUG/Albrecht standard complexity-weight table is adopted as the "reasonable" weight assignment the question invites.

Find. The completed count table (Simple/Average/Complex/Total per component, and the count total, i.e. the Unadjusted Function Points, UFP), the adjustment using five chosen GSCs, and the resulting cost estimate the question's opening sentence asks for.

Approach. Classify each distinct external input, output, inquiry, and logical/interface file the three use cases require as Simple, Average, or Complex by the data elements and files it touches, weight and sum them (UFP), then choose five of the fourteen GSCs, rate each 0–5, and apply the resulting adjustment.

1. Classify the External Inputs (EI). Register Outpatient (four data elements: patientId, name, apptTime, doctorId) is rated Average (1). Register Inpatient (more elements plus a bed-allocation lookup): Complex (1). $$EI = 1(4) + 1(6) = 10$$
2. Classify the External Outputs (EO). Bed-assignment notification to the receiving department (derived, references two files): Average (1). Dispatch notice to the doctor (a plain routing message): Simple (1). $$EO = 1(5) + 1(4) = 9$$
3. Classify the External Inquiries (EQ). Checking bed availability (single-file retrieval): Simple (1). Checking a patient's current status (cross-references Visit/Admission): Average (1). $$EQ = 1(3) + 1(4) = 7$$
4. Classify the Internal Logical Files (ILF). The Patient/Visit file (five elements): Average (1). The Admission/Bed file (more elements, tracks allocation state): Complex (1). $$ILF = 1(10) + 1(15) = 25$$
5. Classify the External Interface Files (EIF). An externally-maintained physician-scheduling feed referenced when dispatching an outpatient: Simple (1). $$EIF = 1(5) = 5$$
6. Sum the Unadjusted Function Points. $$UFP = EI + EO + EQ + ILF + EIF = 10 + 9 + 7 + 25 + 5$$ $$\boxed{UFP = 56 \text{ function points}}$$
7. Choose five adjustment factors and assign values. Of the fourteen General System Characteristics (each rated 0–5), five are selected as most relevant to a hospital registration system:

   GSC (chosen)	Rating (0–5)	Rationale
   Reliability	5	A lost or duplicated bed allocation has direct patient-safety consequences.
   Performance	4	Part (a)'s 60-second dispatch-notification quality requirement is demanding.
   Online data entry	5	All three use cases are interactive, online transactions with no batch component.
   Multiple sites	3	Multiple departments/wards consult the same bed and patient data.
   Operational ease	3	Clerks need a simple registration workflow usable with minimal training.

   $$TDI_5 = 5 + 4 + 5 + 3 + 3 = 20$$
8. Apply the adjustment. $$CAF = 0.65 + 0.01 \times TDI_5 = 0.65 + 0.01(20) = 0.85$$ $$AFP = UFP \times CAF = 56 \times 0.85$$ $$\boxed{AFP = 47.6 \text{ adjusted function points}}$$ The five GSC ratings are project-specific judgement calls (arbitrarily but reasonably assigned, as the question invites).
9. Convert to effort and cost. The question asks for a cost estimate, which needs an organisational productivity rate and labour rate; neither is given, so Pressman's worked-example values are adopted as stated assumptions: 6.5 FP per person-month and a burdened labour rate of $8,000 per person-month. $$E = \frac{AFP}{6.5} = \frac{47.6}{6.5} = 7.32 \text{ person-months}$$ $$C = 7.32 \times 8000$$ $$\boxed{C \approx 58{,}600 \text{ dollars (about 1,230 dollars per FP)}}$$ With the organisation's own historical productivity the same AFP converts directly; the count and weighting method is what the question grades.