Investigation & Research Methods
Why Research Matters in Design
Every successful product begins with research. Before a designer picks up a pencil or opens CAD software, they need to understand who they are designing for, what problem they are solving, and what already exists on the market. You need to understand how primary data and secondary data are used to inform the design process.
Primary data is gathered first-hand (surveys, interviews, testing), while secondary data comes from existing sources (books, websites, databases). Designers use both to build a complete picture of user needs.
Primary Research Techniques
Primary research gives designers direct, up-to-date information about their target users.
Market research involves collecting data about consumer preferences, buying habits, and existing products. Designers use questionnaires, online surveys, and face-to-face interviews to gather opinions directly from potential users. Interviews are particularly useful because the designer can ask follow-up questions and observe body language, giving richer data than a written survey alone.
When analysing questionnaire responses, designers create frequency tables to identify patterns. For example, if 80% of respondents say they want a lightweight product, that becomes a key specification point.
Ergonomics is the study of how people interact with products. Designers consider factors like grip size, viewing angles, and reach distances to ensure products are comfortable and safe to use. Anthropometric data provides body measurements from large population samples — heights, hand spans, sitting heights — that help designers size their products appropriately.
Percentiles divide the population into 100 groups by measurement. Most products are designed for the 5th to 95th percentile, meaning they suit 90% of the population. A chair designed only for the 50th percentile (average) would be uncomfortable for both shorter and taller users.
Focus Groups & Product Analysis
Focus groups bring together a small group of target users to discuss a design concept or existing product. The designer facilitates the discussion and records responses. This qualitative data reveals attitudes and feelings that surveys often miss. Product analysis involves systematically evaluating existing products against criteria such as function, aesthetics, cost, materials, and environmental impact.
Product analysis helps designers identify strengths and weaknesses in existing solutions. By comparing products using a comparative chart of performance criteria, designers can spot gaps in the market and opportunities for improvement.
Secondary Research Sources
Secondary research uses information that already exists. This includes published books, academic journals, manufacturer datasheets, government statistics, and online databases. It is quicker and cheaper than primary research but may be out of date or not specific to the designer’s exact needs. The best approach combines both types — secondary research to build background knowledge, then primary research to fill gaps.
Writing a Design Brief & Specification
Once research is complete, the designer writes a design brief — a concise statement of the problem and the proposed solution. This is followed by a detailed design specification listing measurable criteria the product must meet, such as dimensions, materials, weight limits, target cost, and user requirements.
A good specification is specific and measurable. “The product should be lightweight” is vague. “The product should weigh no more than 500 g” is measurable and testable. Designers may also modify their brief as research reveals new information — this is a normal part of the iterative design process.
A design brief outlines the problem in broad terms. A design specification lists precise, measurable requirements. Both may be revised as the project develops.