Observe Vertical Backrest Positioning Directly
Start by identifying the height control and confirming its operation. Establish the available range and any defined positions before comparing the result with users. The presence of height adjustment does not establish how far the backrest travels, how the setting is retained or which operating method is involved.
Ask the person to describe contact with the backrest at different positions. Record those observations without calling them lumbar support. This keeps the assessment accurate while recognising that backrest placement still matters within the complete sitting arrangement. Compare settings during the same task so changes can be understood in a consistent practical context.
Keep Height Adjustment Distinct From Support Features
Height-adjustable backrest office chairs without lumbar support should be described through their confirmed characteristics. Vertical movement is available, while lumbar support is absent. Neither fact establishes the backrest's shape, recline functions or other movements, so review those details independently if they matter to the workplace brief.
Do not infer that raising or lowering the backrest creates a separate support feature. Instead, assess how the existing surface relates to the user in each position. Ask specific questions about contact and working posture, and note whether the person changes their sitting position when returning to ordinary desk activities after making an adjustment.

