Handbook of Management Scales/JIT delivery by suppliers
JIT delivery by suppliers (alpha > 0.7; composite reliability = 0.66; average variance extracted = 0.39) 
The research takes a step toward clarifying the concept of lean production and develops and validates a multi-dimensional measure of lean production. The 10 distinct dimensions of a lean system are continuous flow, customer involvement, employee involvement, JIT delivery by suppliers, pull, set up time reduction, statistical process control, supplier development, supplier feedback, and total productive/preventive maintenance.
Lean production is an integrated socio-technical system whose main objective is to eliminate waste by concurrently reducing or minimizing supplier, customer, and internal variability. This dimension of lean production is about ensuring that suppliers deliver the right quantity at the right time in the right place.
Please indicate the extent of implementation of each of the following practices in your plant. (1) no implementation; (2) little implementation; (3) some implementation; (4) extensive implementation; (5) complete implementation.
- Suppliers are directly involved in the new product development process.
- Our key suppliers deliver to plant on JIT basis.
- We have a formal supplier certification program.
- Shah/Ward (2007): Deﬁning and developing measures of lean production. Journal of Operations Management, Vol. 25, No. 4, pp. 785-805.
Both composite reliability and average variance extracted are too low. Especially for the first and third item it is questionable if the scale really measures just-in-time delivery.