D: Strand 1

Design Testing Methods

Criterion D, Strand 1:

Design detailed and relevant testing methods, which generate data, to measure the success of the solution.

Command Terms:

Design Display information in a diagrammatic or logical for

How to Complete this strand:

Now that you have decided what it is you are going to evaluate you need to plan how you are going to do it. You will need to use a range of different techniques. Some will work better than other depending on what it is that you want to find out. The main strategies that are available to you are:

User trip/User trial

Questionnaires

Product Comparison

Analysis of Data

Product Testing

User trip/User trial

These are quite similar and generally used to evaluate similar factors but are conducted in a slightly different way. A User trial involves watching a variety of people use your product. It is important that you plan the user trial carefully and have a list of actions that you want the person to perform and questions you want them to answer. You need to ensure that you observe the user closely so that problem areas can be identified as well as clearly recording their answers to your questions. A user trip is a similar alternative but is only carried out by one person, usually the writer of the report. The user will use the product and record any relevant information. The disadvantage of this is you only get one persons opinion.

Survey/Questionnaires

What is a survey?

The survey method is a research method, a tool, used to collect information from a representative sample of a population. This collection of information can be used to learn about the user's self-reported attitudes, opinions, and behaviors. Surveys can be distributed online, in-person, on paper, or even over the telephone .

Questionnaires allow designers to gain information from a wide range of people. It is important that you think carefully about the questions you need to ask and ensure that it is possible for the person to answer them without having used the product. Questions should be quick to answer so that people don’t have to take up too much of their time to complete the questionnaire.

Product Comparison

This can be used to compare your product to other similar ones on the market. It is particularly useful when looking at the functions and features of a product and its value for money. Think carefully about what elements you want to compare and be sure to compare it to at least 2 other products. It is usually best to present your findings in a table.

Analysis of Data

There are three common ways of analysing data in respect to evaluating a product. The first relates to ergonomics and anthropometric data. It is possible to take measurements of parts of your product and compare these to the data given in the ergonomics books to see how well this information has been considered when designing the product. The second from of analysing data is to use existing customer reviews of a product and analyse what this can tell you about a product. You can obtain this information from most websites that sell the product and it can be good for identifying issues that you may not have considered. But BE CAREFUL do not solely rely on one website and make sure you read the good and bad reviews that a product has been given before drawing any conclusions. You can also analyse data with reference to materials. Data sheets on the properties of materials can be looked at to help determine whether or not the most appropriate material has been used.

Product Testing

This is not suitable for all products and you need to think carefully about the timing of when you conduct and product testing particularly as it may result in the product becoming damaged. Some of the most common product tests are:

Drop testing – this is where a product is dropped from a variety of heights onto different surfaces and then inspected for damage (think mobile phone cases)

Water resistance – items can have a material placed inside them then they are sealed and submerged in water once removed the inner material is inspected for signs of moisture

Functional testing – where a product is tested to ensure it does what the manufacturers claim e.g. using a Stanley knife to cut through the range of materials that it should cope with

Seating Example

seating examles _testing.pdf

Likert Scale

One form of measurement is the Likert Scale and it is so commonly used that you have probably taken a survey that used a Likert Scale before! Have you ever been asked to complete a series of statements that use a rating scale to gauge your levels of satisfaction or agreement or your attitudes about frequency or importance?

Several considerations to take into account when using this method include:

Some personalities have a tendency to avoid “extremes.” Such personalities select answers in the middle of the scale. A way to decrease this tendency is to make the survey an anonymous survey.
Previous questions can influence participant’s answers or thoughts. To counteract this, avoid the use of leading or subjective statements.
The scale cannot capture the exact attitude of an individual, it is only an estimate of attitude. Open questions can be used at the end of the survey to gain information on exact attitudes (see next section).

When designing a Likert Scale, it is common to use a five-point or seven-point scale. Each point on the scale is assigned a number as seen below (1 = Strongly Agree, etc). These correspond with a direction that measures intensity (strength of feeling) in positive and negative directions. Here’s an example of the five-point and seven-point scales:

Sample

2) Rate the chair out of 5 for the following points where 5 is the best and 1 is the lowest.

Color

Looks comfortable

Overall appeal

Reverse Scoring

Participants are asked to rate the direction (strength of feeling) of the statement e.g. positive to negative.

Report abuse