Census Research Helps
There are numerous and excellent resources covering a variety of methods for efficiently researching the U.S. census. But as is often the case, the best offense is a good defense, and the best way to approach your research is to carry a general knowledge of the difficulties associated with the project.

• Assuming that the information in the census records is always correct. The enumerator may have taken your ancestor's information from your ancestor's neighbors. Your ancestor may not have spoken English well—or at all—or could have misunderstood various questions. And, the math skills of many census takers was poor, to say the least. Verify all census information with other sources.
• Assuming that the census indexes and Soundexe codes are accurate. The information in the Soundex is based on the information in the index, and the index is based on a manual transcription of the actual census. There are errors and omissions in all of the census indexes. If you know (or strongly suspect) that your family was living in a particular county at the time of the census, browse all of the census images for that locality.
• Assuming that children belong to the couple with whom they are enumerated (unless relationships are specified). They may be nieces and nephews, grandchildren, or even unrelated. Enumerators sometimes made assumptions of their own while completing the enumeration.
• Assuming that the enumerated children were the offspring of the current wife. They may be, but sometimes are not. Many early-American women died in childbirth, leaving the father with young children to care for. The solution was to find a wife—so re-marriage was frequent.
• Assuming that all the people listed in the families on the 1790 to 1840 censuses are related. They could have been farmhands or workers living with the family. Co-opts and communes were more common in earlier days, and at times, several families resided together.
• Assuming when a head-of-household is no longer enumerated with the family that he or she is dead. The parents may have gone to live with a son or daughter. Always search for them in the homes of their children.
• Assuming that a person listed in the census was still living at the time of the census. The enumerator was instructed to take down the names of the family members that were living on the official date of the census, not the day of the visit.