Comparing the usefulness of rules & no rules in engineering design brainstorming?

The most common early-stage design technique is brainstorming which combines an informal approach to problem solving with a set of rules. These brainstorming rules were created by Alex Osborn in 1953 to encourage participants to contribute, by banning criticism and negativity (blocks), resulting in the generation of a larger quantity of ideas. Significant research has been conducted into engineering design brainstorming, specifically exploring the effects of the brainstorming rules. The results have varied, with Meadow and Osborn providing an anti-criticism standpoint, whereas Sonalkar, Bergner and Nemeth provide a pro-blocking (pro-criticism) standpoint.

The research presented in this paper aimed to understand the effects of brainstorming with, and without rules, and compares the productivity of each condition. Furthermore, the research explored the effects of specific types of criticism .

For the research several stimulating problems, previously used in design engineering, were utilised with and without brainstorming rules (Natural condition) to test the hypotheses. Two optimally-sized, 3-participant groups were chosen with similar educational experience to balance overly strong and weak participants whilst ensuring a positive group dynamic increased the reliability of results. Video recordings were taken of the eight separate design sessions and, using the Interaction Dynamic Notation (Solnakar, 2012), a full visual representation and transcript were created. The notation aided in the analysis which found that the Natural condition generated 7.75 more ideas per test than the Rule condition. Furthermore, the Natural condition generated a higher percentage of good ideas (50% compared to 30%) and more good ideas (4.25 per brainstorming session). The observations highlighted the specific blocking/criticism effects which generated a significant number of ideas directly, by overcoming blocks, or indirectly, by blocking-inspired conversation.

The controlled results also showed that the Natural condition evaluated the ideas more effectively, choosing 5 more good ideas and 4 more of the best ideas for progression; however the results were unreliable due to the basic nature of the phase which disallowed direct comparison to industrial design processes. Finally, the observations highlighted three major types of blocking. Negativity represents the first blocking type which disrupted the conversation flow and brainstorming environment. Criticism was the most commonly used block and regularly resulted in a creative ‘overcoming’ expression, however occasionally promoted a response similar to negativity. Finally, constructive criticism was the least common type of blocking however the most effective in terms of increasing idea generation. The observations could provide some insight for the generation of an updated set of brainstorming rules.

Although the majority of results were conclusive, some inconclusive findings were highlighted which reduced the overall reliability of the results. To alleviate the unreliability more tests should be undertaken, using two problems as opposed to four, to increase the accuracy and ensure the conclusions are robust. Furthermore, if a full inter-rater reliability check was undertaken the accuracy and reliability of the results could be validated.