Search engine optimization (SEO) experts say domain-level link authority features—such as the quality of links to a website and its overall PageRank—have the biggest positive impact on Google's algorithm for rankings, according to a recent report from Moz.

The report was based on data from an in-depth survey of 150 marketing professionals who specialize in search engine optimization.

Each respondent rated the relative levels of influence exerted by broad search ranking factors on a scale of 1 (not influential) to 10 (highly influential).

Domain-level link authority features received an average score of 8.22, the highest of any factor. Page-level metrics ranked a close second (average score of 8.19), followed by page-level content/keywords (7.87).

Detailed definitions of each factor of Google's algorithm can be found in the full report.

Respondents were also asked to predict how the importance of certain factors accounted for in Google's search algorithm might change over the next 12 months.

Mobile friendliness is seen as the factor most likely to become more impactful (88% of respondents believe its importance will increase), and paid links are seen as the feature most likely to become less impactful (55% believe their importance will decline).

About the research: The report was based on data from an in-depth survey of 150 marketing professionals who specialize in Search Engine Optimization.