A slowdown at its qualitative research business has prompted Cello to caution like for like gross profits are down by around 10% year on year, with operating margins also squeezed.The market research group has cut costs to offset the downturn. Like for like professional costs have been reduced by around 7%. The cost reduction measures outlined above have resulted in an exceptional cost of around £0.4m in the first half. Overall, Cello says a full year headline operating profit in line with the current market consensus is achievable."Core revenue visibility remains solid as contract retention has proved to be good. The group has also continued to take prudent action to adjust the cost base and remains alert to taking further action where necessary," it adds.