"Continuing global economic uncertainty has led to marketers adopting a generally conservative outlook over recent months," the study said.
"It remains to be seen if the recent announcements of bond-buying schemes from central banks in Europe and the US, which have resulted in sharp gains on global stock markets, will lead to an improvement in the broader economy and increased marketing budgets in the months ahead."
In regional terms, the Americas were unchanged measured against the previous month, on 53.5 points, while Asia Pacific recorded a 3.1 point leap, to 49.1 points.
The reading in Europe was significantly below the 50-point mark indicating neutral sentiment, and came in at 44.8 points. However, this did equate to a jump of 3.9 points since August.
By medium, the internet should retain its position as the primary driver of any growth, having yielded an index score of 74 points. Mobile, which is broken out separately from the web, registered 67.2 points.
Elsewhere, the outlook improved slightly for television, which logged 47.2 points in the latest research round, compared with 46.2 points a month earlier. Press also saw a lift of 2.3 points, albeit to only 35.3 points.
When assessing trading conditions, the panel returned a rating of 54.7 points, up by 0.3 points from August. Totals hit 63 points in the Americas, and reached 54.8 points in Asia Pacific, as well as 51.3 points in Europe.
Turning to staffing levels, the global index stood at 56.1 points, off from 56.6 points the previous month. The Americas posted the best score, 62.2 points, with Asia Pacific on 57.5 points and Europe on 54.4 points.
Overall, the headline GMI, which combines all of these categories, climbed by 0.5 points month on month, to 52.9 points.
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