One of the precepts of Total Quality Management,
and now continued into Six
Sigma, is that groups generally
make better decisions than individuals,
and that the group should be cross-functional.
It should include everybody who can contribute,
regardless of their position in the hierarchy,
rather than just specialized individuals.
This section includes a selection of tools
that are best used by groups. They are either
graphical methods that promote group input,
or ways of capturing the individual inputs
and then refining them to discover the best
solution, and to achieve 'buy in' to that
A team-based method of organizing large
amounts of data. Typically, brainstormed
ideas are written on ‘sticky notes’. These
are stuck to a wall and progressively organized
into logical groupings by the participants.
A method of encouraging a team to generate
creative ideas. All ideas are written down,
and no idea, however apparently silly, is
criticized. The list can be culled later
using other methods e.g. multivoting.
and Effect Diagrams
A graphical tool used to list
and categorize possible causes of a problem.
It looks like a fish skeleton and is sometimes
called a ‘fishbone diagram’.
The main categories are often selected
as Methods, Equipment, Personnel, Materials,
but this is optional:
See Cause and Effect Diagram
Design Failure Mode and Effects
Analysis. This applies when FMEA is carried
out at the design stage and looks at ways
the item can fail during use. Potential
failure modes include failures from the
item becoming defective and through the
way the item is used.
The failure modes for a step
ladder could include potential failure because
a component could corrode and fail. They
could also include a potential failure because
the user's foot could slip on the treads.
Mode and Effects Analysis
A method for evaluating risk. Each potential
failure mode is evaluated for:
S: the severity of the
consequences if it does occur
O: the probability of
D: the probability of
detection before shipping.
Each of these is rated on a scale from
1 to 10, and the three values multiplied
to find the Risk Priority Number (RPN).
If the RPN is above a specified threshold,
action is taken to reduce it. The FMEA is
often used as the basis for Control.
See Cause and Effect Diagrams
See Failure Modes and Effects Analysis
A team based method of brainstorming the
'drivers' and 'restraints' that affect progress
to a desired goal: