I'm reading a stress-rating scale. "Change in work" is scored 36 while "Change in working conditions" is scored 20. But isn't "Change in work" the same idea as "Change in working conditions"?
Change in work, as Mike said, means getting an entirely new/different job, which can certainly be stressful. "Change in working conditions" refers to changes in your current job, such as you once had your own office, but now you have to work in a tiny cubicle. Or it could be that your company used to pay for your health insurance, but now instead they are deducting it from your salary.