The purpose of writing an evaluation report is usually to change things. This may mean considerable expense and inconvenience, so your report has to be convincing or it will be dismissed or ignored. Here is an extract from instructions given to test pilots on how to write reports after flight tests. Exactly the same principles should apply to reporting on usability evaluation tests.
1 The end product of all flight testing is the test pilot’s written report on the results of his work in the air. No matter how skilful he is as a pilot, his efforts will be wasted if he is unable to communicate his findings and persuade others of his viewpoint. The art of effective report writing is as important to the test pilot as a sound knowledge of his aircraft or the theory and practice of test flying.
2 Proficiency in report writing can only be acquired through practice and a thorough understanding of the basic principles involved. Reports thus constitute a major part of the ETPS syllabus, the primary aims being to give students such practice and to ascertain whether the test exercise has been properly understood . . . in addition, students will practice verbal presentations for the same reasons; the basic rules of report writing also apply to such presentations.
3 The flight test report follows the basic conventions of good English prose with particular emphasis on the following factors:
ACCURACY Facts and wording must be accurate. Opinions and deductions must be distinguishable from facts. The reader’s confidence in your judgement and your report will be undermined if he discovers errors of fact.
BREVITY The reader must be informed in the shortest way consistent with accuracy and clarity. His time is wasted by ‘rambling’ statements, unnecessary repetition, the inclusion of non-essential information and verbose phrases. Be concise; omit irrelevant information. Careful planning and editing are essential.
RELEVANCE Any irrelevant word, phrase or idea must be excluded. Avoid any tendency to include information outside the terms of reference of the report merely to demonstrate your powers of observation or the comprehensive nature of the flight tests performed.
LOGIC Conclusions, from which costly and time-consuming modifications may be recommended, must be fully supported by the facts obtained in the test. Conclusions should be contained in sentences and paragraphs which follow a logical sequence related directly to the argument.
The Successful Report
If your report is to be effective in convincing the reader of the soundness of your observations, you should ensure that the answer to the following questions is YES before submitting it:
a Does my report fulfil the purpose for which it is intended?
b Are my data and observations accurate?
c Does my writing clearly say what I want to be known?
d Will the reader be able to understand it?
e Will the reader enjoy it?
Empire Test Pilot School, Flying Wing Notes, Chapter 1 (extract), circa 1986, in: Johnson, Brian, 1986, Test Pilot, BBC Publications, London, p.66.