Almost every BSIT, BSCS and BSIS capstone in the Philippines ends with the same sentence in Chapter 3: “the system was evaluated using ISO 25010.” A panel with a software engineer on it now asks three follow-up questions — which edition, which characteristics, and who wrote the items — and the group usually cannot answer any of them. The table below compares the four instruments capstone groups actually reach for, so that the evaluation chapter names the right one for the right reason before the proposal is locked.
The comparison table
| Instrument | What it measures | Who answers it | Items and scale | Original source to cite | Cost and permission |
|---|---|---|---|---|---|
| ISO/IEC 25010 product quality model | Software product quality across nine characteristics: functional suitability, performance efficiency, compatibility, interaction capability, reliability, security, maintainability, flexibility and safety | IT experts, developers, the adviser; end users only for a subset | No items — it is a model of characteristics, and you write or adopt items for each one you use | ISO/IEC 25010:2023, Systems and software Quality Requirements and Evaluation (SQuaRE), Product quality model | The standard is a paid document from ISO; the characteristic names are public and citable from the abstract |
| System Usability Scale (SUS) | Perceived usability as a single score from 0 to 100 | End users, after a task session | 10 items, five-point agreement scale, alternating positive and negative wording | Brooke (1996), “SUS: A quick and dirty usability scale” | Free to use; cite the source |
| Post-Study System Usability Questionnaire (PSSUQ) | Perceived usability in three factors: system usefulness, information quality, interface quality | End users, after a task session | 16 items in the current version, seven-point scale | Lewis (2002), International Journal of Human-Computer Interaction, 14(3–4), 463–488 | Free to use; cite the source |
| Technology Acceptance Model (TAM) | Whether users are likely to adopt the system: perceived usefulness, perceived ease of use, attitude, intention | Intended users, before or after limited use | Six items each for perceived usefulness and ease of use in the original scales, seven-point scale | Davis (1989), MIS Quarterly, 13(3), 319–340 | Free to use; cite the source |
The fault in most capstone evaluation chapters is a category error. ISO 25010 is a quality model: it tells you what to measure, not how, and it has no questionnaire. SUS, PSSUQ and TAM are instruments: validated sets of items with published scoring. A capstone that says “evaluated using ISO 25010” and then hands respondents a five-point questionnaire has, in fact, evaluated with a researcher-made instrument loosely organised around ISO headings, and the panel is entitled to ask for its validation.
The ranked shortlist
1. ISO/IEC 25010:2023 — for the expert evaluation, and only with the current edition
Use it when your panel or your department’s capstone guidelines require a software quality evaluation by IT experts, which is the case in most BSIT and BSCS programs following the CHED policies, standards and guidelines that made the capstone a program requirement. Name the 2023 edition explicitly, because the revision changed the model: usability became interaction capability, portability became flexibility, and safety was added as a ninth characteristic. A manuscript that lists the 2011 edition’s eight characteristics while citing “ISO 25010” without a year is the single most common thing a software-engineer panelist circles.
Suits: expert evaluation of the product by developers, IT faculty and the adviser, three to ten respondents, characteristic by characteristic. Falls short: it gives you no items, so every item you write is researcher-made and needs validation; end users cannot rate maintainability or security meaningfully, so do not give them the full model; and the standard itself is a paid document, so cite the characteristic names from the published abstract rather than reproducing text you have not read.
2. System Usability Scale — for the end-user evaluation, when you need one number
SUS is ten items, takes two minutes, and produces a score from 0 to 100 that the whole panel understands. It has been in continuous use since Brooke published it in 1996 and a widely used benchmark from Sauro’s analysis of hundreds of studies places the average at 68, which gives your Chapter 4 a comparison point that a researcher-made questionnaire never has. Score it the published way — subtract one from odd items, subtract even items from five, sum, multiply by 2.5 — and report the mean SUS score with its standard deviation.
Suits: any capstone with end users who complete tasks in the system: students using an enrolment portal, clinic staff using a records system, barangay staff using an information system. Falls short: it is one score and cannot tell you which part of the interface failed; it says nothing about functionality, security or performance; and its alternating wording confuses respondents with limited English unless you translate and pilot it.
3. PSSUQ — when the panel wants usability broken into parts
The PSSUQ gives three subscale scores alongside an overall score: system usefulness, information quality and interface quality. That structure answers the question SUS cannot — was it the error messages, the layout or the workflow — and it maps well onto the revision phase every capstone goes through after the initial demo. Lewis’s 2002 article in the International Journal of Human-Computer Interaction reports its psychometric properties and is the citation to use.
Suits: capstones with a formal user-testing session and a revision cycle, or a panel that wants diagnostic detail. Falls short: at 16 items on a seven-point scale it takes longer than SUS, and the seven-point format has to be reproduced exactly — collapsing it to a five-point Likert breaks the comparison with published norms.
4. Technology Acceptance Model — for adoption, not quality
TAM answers a different question from the other three: will the intended users actually adopt the system? Davis’s 1989 scales for perceived usefulness and perceived ease of use are short, well-validated and free, and they suit a capstone deployed into a real office where adoption is the risk — a barangay records system, a school clinic, a cooperative’s inventory. The two constructs also give you a hypothesis to test, which is rare in a capstone: perceived ease of use is expected to predict perceived usefulness and intention.
Suits: capstones deployed to real users with a research question about acceptance or intention to use. Falls short: it does not evaluate the software’s quality at all, so it cannot replace the expert evaluation; and its later extensions (TAM2, UTAUT) add constructs your sample size will not support.
The recommendation
For a typical Philippine capstone — a web or mobile information system built for one office, school or barangay, defended in front of a panel that includes at least one software engineer — use two instruments for two respondent groups: ISO/IEC 25010:2023 characteristics rated by IT experts using items you have validated, and the System Usability Scale answered by end users after a task session. Add the PSSUQ instead of SUS if the panel wants diagnostic detail, and add the TAM scales only if adoption is a stated research question. Never present one questionnaire given to everybody as “ISO 25010 evaluation”.
How to write the items for the ISO characteristics
Because the standard supplies no items, the items are yours, and a panel will treat them as a researcher-made instrument. Three rules keep it defensible. Write two to four items per characteristic you use, each describing one observable behaviour of the system rather than the characteristic’s name — “the system produces the correct total when a payment is recorded” rather than “the system is functionally suitable”. Have the items validated by three IT faculty and revise on their comments, then pilot with respondents outside your final sample and report Cronbach’s alpha per characteristic. Keep the response scale consistent and state its verbal anchors in Chapter 3.
Choose characteristics by what your respondents can actually observe. Experts who have read the code can rate maintainability; users who have only used the interface cannot. The procedure for validating researcher-made items, including the pilot and the reliability run, is the same one described for survey instruments in the guide to building a thesis questionnaire item by item, and the adopt-versus-adapt rule that applies to SUS, PSSUQ and TAM — use the published wording unless you can justify the change and re-pilot — is the same one set out for adopting a standardized scale in a thesis.
How to report the evaluation in Chapter 4
Report the expert evaluation as a table with one row per ISO characteristic: mean, standard deviation, verbal interpretation, and the number of expert respondents. Report SUS as the mean score with its standard deviation and the benchmark you are comparing against. Report the PSSUQ as three subscale means and an overall mean. Report TAM constructs as means and, if the sample permits, the correlation between perceived ease of use and perceived usefulness. The descriptive statistics and the reliability run are two menu paths in the walkthrough on analysing thesis data in SPSS step by step.
One paragraph the panel always wants and the manuscript rarely has: what you changed in the system because of the evaluation. A capstone is a development project; an evaluation that produced no revision is an evaluation that was not read.
Citing the instruments in APA 7th and IEEE
Capstone documentation in the Philippines is written in APA 7th in most colleges and in IEEE in some engineering-affiliated IT programs; the differences that cost marks are compared in the guide to APA versus IEEE for a Philippine capstone. The three entries below cover the instruments in APA 7th:
Brooke, J. (1996). SUS: A quick and dirty usability scale. In P. W. Jordan, B. Thomas, B. A. Weerdmeester, & I. L. McClelland (Eds.), Usability evaluation in industry (pp. 189–194). Taylor & Francis.
Davis, F. D. (1989). Perceived usefulness, perceived ease of use, and user acceptance of information technology. MIS Quarterly, 13(3), 319–340. https://doi.org/10.2307/249008
Lewis, J. R. (2002). Psychometric evaluation of the PSSUQ using data from five years of usability studies. International Journal of Human-Computer Interaction, 14(3–4), 463–488.
For the standard, cite the organisation as author: International Organization for Standardization. (2023). Systems and software engineering — Systems and software Quality Requirements and Evaluation (SQuaRE) — Product quality model (ISO/IEC 25010:2023). Cite the edition you actually used, and do not paraphrase content you have only seen in a blog.
What this decision is not
Choosing the evaluation instrument does not settle whether the project is a thesis or a capstone, what the documentation chapters are called, or how the working system is mapped onto them — those questions are answered in the explainer on the difference between a thesis and a capstone project and in the guide for groups whose system works but whose documentation is empty. The instrument decides only how Chapter 4 will be filled, and it is the decision most often made a week before the defense, when it should have been made at the proposal.
Write the evaluation section around the instrument you chose
Tesify drafts the Chapter 3 evaluation procedure and the Chapter 4 results write-up from the instruments you name — the ISO/IEC 25010:2023 characteristics you selected, the SUS or PSSUQ scoring rule, the TAM constructs — in the capstone documentation structure Philippine IT programs expect, and builds the APA 7th or IEEE reference entry for each source as you go. Over 9,000 students have used it to write more than 15,000 chapters, and every word is still written by you.
Start your capstone documentation on Tesify · Tighten the evaluation chapter with the AI editor
Frequently asked questions
Is ISO 25010 a questionnaire?
No. ISO/IEC 25010 is a product quality model that names nine characteristics of software quality. It contains no items, so any questionnaire organised around it is researcher-made and must be validated and piloted like any other instrument.
What changed in ISO/IEC 25010:2023?
The 2023 edition renamed usability to interaction capability, renamed portability to flexibility, and added safety as a ninth characteristic. Cite the edition you used; listing the 2011 edition’s eight characteristics under a 2023 citation is an error panels catch.
Can end users evaluate using ISO 25010?
Only for the characteristics they can observe, chiefly interaction capability and functional suitability. Maintainability, security and flexibility require expert respondents. For end users, a validated usability instrument such as SUS or PSSUQ is the better choice.
What is a good SUS score for a capstone system?
A score of 68 is the widely cited average from Sauro’s analysis of published studies; scores above it are better than average. Report the mean and standard deviation, and compare against that benchmark rather than inventing a verbal scale.
Can I use TAM instead of ISO 25010?
Not as a replacement. TAM measures acceptance — perceived usefulness, perceived ease of use and intention to use — not software quality. Use it alongside an expert quality evaluation when adoption is part of your research question.
Do I need permission to use SUS, PSSUQ or TAM?
All three are published in the open literature and are used freely in academic research with citation. The ISO standard itself is a paid document; the characteristic names are citable from the published abstract, but do not reproduce the standard’s text.
How many expert respondents do I need for the ISO evaluation?
Three to ten is typical for a capstone: developers, IT faculty and the adviser. State who they are and why they qualify. Do not inflate the expert group with classmates who did not examine the system.