SYDNEY (AP) -- By the time the ambulance showed up to the house, the old woman's screams were, as the paramedics would later tell it, already at a 10 out of 10.
On a bed in the foyer lay 88-year-old Cynthia Thoresen, her eyes screwed up in agony, her fists clenched, with an untended broken leg. Feces caked her body, from her arms down to her feet, filling the crevices between her toes and under her fingernails.
The fact that Cynthia even lived in the house was a surprise to most of the neighbors. None had ever seen her. None had any idea she'd spent her final days in hellish pain after a fall. None knew that her daughter and caretaker, Marguerite Thoresen, had waited weeks before calling for help, or that the help would come far too late.
In the end, Cynthia Thoresen joined a large and growing cohort of elderly people across the world who live -- and increasingly die -- in silence. They are unseen and unheard, left to fend for themselves against a problem society has barely begun to notice, let alone fix: elder abuse.
This type of abuse, which in many cases includes neglect, is still so hidden that it is hard to quantify. But the broad picture gleaned from hundreds of interviews and dozens of studies reviewed by The Associated Press is clear: Tens of millions of elders have become victims, trapped between governments and families, neither of which has figured out how to protect or provide for them.
EDITOR'S NOTE -- As the world ages faster than ever, who will care for the old? This story is part of an occasional series about elder neglect and abuse worldwide.
Most of the elderly live with relatives or at home, and researchers estimate at least 4 to 10 percent of them are abused, likely much more. Even by the lowest count of 4 percent, that means about 30 million people.
The demographics alone show clearly that the problem is growing. By the year 2050, there will be more old people on earth than children for the first time in history, because of rising life spans and falling birth rates.
Australia, where Cynthia Thoresen lived, is a developed, wealthy nation considered progressive in its treatment of seniors. But even in high-income countries, the rate of abuse is 4 to 6 percent, according to the World Health Organization. And even here, the system failed Cynthia, over and over again, in life and in death.
"Nothing in the past has disturbed me like this job disturbed me," paramedic Christopher Curtis told police. "I've not seen anyone, regardless of their age, that could withstand the level of pain inflicted by a fractured femur for five seconds, let alone three weeks."
And yet Cynthia Thoresen lay helpless for up to three months, screaming into the silent void of a world that had forgotten her.
For some, aging in today's world can be a slow slide into invisibility.
In study after study, elders say they exist in the shadows, at home or in institutions. Their words are dismissed. Even their bodies shrink. Sometimes they become invisible to themselves, as the cruelty of dementia robs them of the memories of who they once were.
This invisibility is reflected in the laws and practices of society.
Information on elder abuse lags decades behind research on child abuse. Only a handful of countries legally require the reporting of suspected elder abuse, compared to dozens for child abuse.
In the U.S., which researchers consider relatively advanced, the government passed the Elder Justice Act in 2010, compared to 1974 for its counterpart on child abuse. No more than two cents of every dollar spent by the federal government on family violence goes to elder abuse. And studies of domestic violence tend not to include victims older than 49.
Researchers can't even agree on who is an elder, let alone what elder abuse is. Depending on the country and culture, the definition ranges from physical and financial abuse to emotional cruelty and even disrespect.
"Here in Canada, millions of dollars have been spent on definitions and they go around in a circle and it drives me crazy," says Elizabeth Podnieks, founder of World Elder Abuse Awareness Day. "It's extremely hard to both identify and to address."
Other data from the World Health Organization, the United Nations, aged care advocates and academics fills in the edges of a hazy but distressing snapshot.